Photosensitive resin composition, method for producing cured product of fluororesin, fluororesin, fluororesin film, bank and display element

ABSTRACT

An object of the present invention is to provide a photosensitive resin composition having good liquid repellency. The photosensitive resin composition of the present invention at least contains a fluororesin having a crosslinking site, a solvent, and a photopolymerization initiator, and the fluororesin contains a repeating unit derived from a hydrocarbon having a fluorine atom.

TECHNICAL FIELD

The present disclosure relates to a photosensitive resin composition anda method of producing a fluororesin cured product.

BACKGROUND ART

An inkjet method is known as a method of forming organic layers having alight emitting function and the like in the production of displayelements such as organic EL displays, micro-LED displays, and quantumdot displays. There are several methods for the inkjet method. Specificmethods include one in which ink dropped from a nozzle into recesses ofa patterned film having recesses and protrusions formed on a substrateis solidified; and one in which a patterned film is formed on asubstrate in advance to provide a liquid-affinity portion havingwettability with ink and a liquid-repellant portion having repellency toink, and ink droplets are dropped onto the patterned film, whereby theink is attached only to the liquid-affinity portion.

Specifically, in the former method in which ink dropped from a nozzleinto recesses of a patterned film is solidified, mainly two methods areapplicable to produce such a patterned film having recesses andprotrusions. One is photolithography in which a surface of aphotosensitive resist film applied to a substrate is exposed to light ina pattern form to form exposed portions and non-exposed portions, andeither exposed portions or non-exposed portions are dissolved in adeveloper and removed; and the other is imprinting that uses a printingtechnique. Generally, after a patterned film having recesses andprotrusions is formed, the entire substrate is subjected to UV-ozonetreatment or oxygen plasma treatment. With the UV-ozone treatment oroxygen plasma treatment, particularly, residual organic matter in therecesses of the patterned film can be removed, and uneven wetting of thedropped ink is reduced. This can prevent defects in display elements.

The protrusions of the patterned film having recesses and protrusionsformed thereon are called banks (partition walls). The banks function aspartition walls that prevent ink mixing when ink is dropped into therecesses of the patterned film. To enhance the effect of the partitionwalls, the substrate surface exposed at the recesses of the patternedfilm is required to have affinity for ink, and upper surfaces of thebanks are required to have liquid repellency.

Patent Literature 1 discloses a photosensitive resin compositioncontaining a vinyl polymer including a side chain having an epoxy group.

Patent Literature 2 discloses a fluorine polymer containing a repeatingunit having a fluorine atom on the main chain, which can be thermallycured at low temperatures (room temperature to 150° C.).

In addition, known examples of compositions for forming banks fororganic EL include compositions containing, as an ink repellent, afluorine polymer having an acrylic structure on the main chain (e.g.,Patent Literatures 2 and 3).

CITATION LIST Patent Literature

-   Patent Literature 1: JP 2016-142753 A-   Patent Literature 2: WO 2018/43165-   Patent Literature 3: JP 2015-172742 A-   Patent Literature 4: JP 2012-108499 A

SUMMARY OF INVENTION Technical Problem

Resin cured products obtained using the resin compositions described inPatent Literatures 1 and 2 do not have sufficient liquid repellency andare hardly usable in applications that require liquid repellency.

The present disclosure aims to provide a photosensitive resincomposition having good liquid repellency.

Solution to Problem

The present inventors conducted extensive studies on the above problems.As a result, they found that the above problems can be solved by aphotosensitive resin composition at least containing a fluororesinhaving a crosslinking site, a solvent, and a photopolymerizationinitiator, wherein the fluororesin contains a repeating unit derivedfrom a hydrocarbon having a fluorine atom.

A fluororesin cured product obtained by curing the photosensitive resincomposition of the present disclosure also has excellent liquidrepellency. Thus, when the photosensitive resin composition of thepresent disclosure is used to form banks for displays such as organic ELdisplays, micro-LED displays, and quantum dot displays, the banks showexcellent ink repellency.

Specifically, the present disclosure is as follows.

[Invention 1]

A photosensitive resin composition at least containing a fluororesinhaving a crosslinking site; a solvent; and a photopolymerizationinitiator,

wherein the fluororesin contains a repeating unit derived from ahydrocarbon having a fluorine atom.

[Invention 2]

The photosensitive resin composition according to Invention 1, whereinthe repeating unit derived from a hydrocarbon having a fluorine atom hasa structure represented by the following formula (1-1):

[Chem. 1]

—CR¹⁻²═CRf₂  (1-1)

wherein each Rf independently represents a C1-C6 linear, C3-C6 branched,or C3-C6 cyclic perfluoroalkyl group or a fluorine atom; and R¹⁻²represents a hydrogen atom or a C1-C6 linear, C3-C6 branched, or C3-C6cyclic alkyl group.

[Invention 3]

The photosensitive resin composition according to Invention 1 or 2,wherein the repeating unit derived from a hydrocarbon having a fluorineatom has a structure represented by the following formula (1-2):

wherein each Rf independently represents a C1-C6 linear, C3-C6 branched,or C3-C6 cyclic perfluoroalkyl group or a fluorine atom; R¹⁻¹ representsa hydrogen atom, a fluorine atom, or a methyl group; and R¹⁻² representsa hydrogen atom or a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup.

[Invention 4]

The photosensitive resin composition according to Invention 2 or 3,wherein Rf in the formula (1-1) or (1-2) is a fluorine atom, atrifluoromethyl group, a difluoromethyl group, a pentafluoroethyl group,a 2,2,2-trifluoroethyl group, an n-heptafluoropropyl group, a2,2,3,3,3-pentafluoropropyl group, a 3,3,3-trifluoropropyl group, ahexafluoroisopropyl group, a heptafluoroisopropyl group, ann-nonafluorobutyl group, an isononafluorobutyl group, or atert-nonafluorobutyl group.

[Invention 5]

The photosensitive resin composition according to any one of Inventions1 to 4, wherein the fluororesin has a fluorine content of 20 to 50 mass%.

[Invention 6]

The photosensitive resin composition according to any one of Inventions1 to 5, further containing a crosslinking agent.

[Invention 7]

The photosensitive resin composition according to any one of Inventions1 to 6, further containing an alkali-soluble resin.

[Invention 8]

The photosensitive resin composition according to any one of Inventions1 to 7, which is cured at a temperature of 140° C. or lower.

[Invention 9]

A method of producing a fluororesin cured product, including:

a baking step of baking the photosensitive resin composition accordingto any one of Inventions 1 to 8 at a temperature of 140° C. or lower forcuring.

[Invention 10]

The method of producing a fluororesin cured product according toInvention 9, wherein in the baking step, the photosensitive resincomposition is baked at 60° C. to 130° C.

[Invention 11]

The method of producing a fluororesin cured product according toInvention 9 or 10, wherein the method includes an exposing step ofexposing the photosensitive resin composition to high energy rays beforethe baking step.

[Invention 12]

The method of producing a fluororesin cured product according toInvention 11, wherein the high energy rays are at least one type of raysselected from the group consisting of ultraviolet rays, gamma rays,X-rays, and α-rays.

[Invention 13]

A method of producing a fluororesin cured product, including:

a film forming step of applying the photosensitive resin compositionaccording to any one of Inventions 1 to 8 to a substrate and heating thephotosensitive resin composition to form a fluororesin film;

an exposing step of exposing the fluororesin film to high energy rays;

a developing step of developing the fluororesin film after the exposingstep in an alkaline aqueous solution to form a patterned fluororesinfilm; and

a baking step of baking the patterned fluororesin film at a temperatureof 140° C. or lower for curing after the developing step to obtain afluororesin cured product.

[Invention 14]

A fluororesin containing a repeating unit represented by a formula (2-1)and a repeating unit represented by a formula (2-2):

wherein R²⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R²⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R²⁻³ and R²⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R²⁻¹, R²⁻³, and R²⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R²⁻⁵ and R²⁻⁶ each independently represent a hydrogen atom or amethyl group; W² is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A² is a divalent linking group and represents a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkylene group in which one or more hydrogenatoms in the alkylene group may be substituted by hydroxy groups or—O—C(═O)—CH₃; Y² is a divalent linking group and represents —O— or —NH—;and n represents an integer of 1 to 3.

[Invention 15]

The fluororesin according to Invention 14, wherein R²⁻³ and R²⁻⁴ eachindependently represent a fluorine atom, a trifluoromethyl group, adifluoromethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethylgroup, an n-heptafluoropropyl group, a 2,2,3,3,3-pentafluoropropylgroup, a 3,3,3-trifluoropropyl group, or a hexafluoroisopropyl group.

[Invention 16]

The fluororesin according to Invention 14 or 15, further containing arepeating unit represented by a formula (2-3):

wherein R²⁻⁷ represents a hydrogen atom or a methyl group; R²⁻⁸represents a C1-C15 linear, C3-C15 branched, or C3-C15 cyclic alkylgroup in which one or more hydrogen atoms in the alkyl group aresubstituted by fluorine atoms; and the repeating unit has a fluorinecontent of 30 mass % or more.

[Invention 17]

The fluororesin according to any one of Inventions 14 to 16, furthercontaining a repeating unit represented by a formula (2-4):

wherein R²⁻⁹ represents a hydrogen atom or a methyl group; each B²independently represents a hydroxy group, a carboxy group,—C(═O)—O—R²⁻¹⁰ wherein R²⁻¹⁰ represents a C1-C15 linear, C3-C15branched, or C3-C15 cyclic alkyl group in which one or more hydrogenatoms in the alkyl group are substituted by fluorine atoms, and R²⁻¹⁰has a fluorine content of 30 mass % or more, or —O—C(═O)—R²⁻¹¹ whereinR²⁻¹¹ represents a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup; and m represents an integer of 0 to 3.

[Invention 18]

A photosensitive resin composition at least containing the fluororesinaccording to any one of Inventions 14 to 17; a solvent; and aphotopolymerization initiator.

[Invention 19]

The photosensitive resin composition according to Invention 18, whereinthe solvent is at least one selected from the group consisting of methylethyl ketone, cyclohexanone, methyl isoamyl ketone, 2-heptanone,ethylene glycol, ethylene glycol dimethyl ether, ethylene glycolmonoacetate, diethylene glycol, diethylene glycol monoacetate,diethylene glycol dimethyl ether, propylene glycol, propylene glycolmonoacetate, propylene glycol monomethyl ether (PGME), propylene glycolmonomethyl ether acetate (PGMEA), dipropylene glycol, dipropylene glycolmonoacetate monomethyl ether, dipropylene glycol monoacetate monoethylether, dipropylene glycol monoacetate monopropyl ether, dipropyleneglycol monoacetate monobutyl ether, dipropylene glycol monoacetatemonophenyl ether, 1,4-dioxane, methyl lactate, ethyl lactate, methylacetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethylethoxypropionate, γ-butyrolactone, and hexafluoroisopropyl alcohol.

[Invention 20]

The photosensitive resin composition according to Invention 18 or 19,further containing a crosslinking agent and an alkali-soluble resin.

[Invention 21]

A fluororesin film containing a repeating unit represented by a formula(2-1) and a repeating unit represented by a formula (2-2A):

wherein R²⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R²⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R²⁻³ and R²⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R²⁻¹, R²⁻³, and R²⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R²⁻⁵ and R²⁻⁶ each independently represent a hydrogen atom or amethyl group; W² is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A² is a divalent linking group and represents a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkylene group in which one or more hydrogenatoms in the alkylene group may be substituted by hydroxy groups or—O—C(═O)—CH₃; Y² is a divalent linking group and represents —O— or —NH—;and n represents an integer of 1 to 3.

[Invention 22]

A bank containing a repeating unit represented by a formula (2-1) and arepeating unit represented by a formula (2-2A):

wherein R²⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R²⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R²⁻³ and R²⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R²⁻¹, R²⁻³, and R²⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R²⁻⁵ and R²⁻⁶ each independently represent a hydrogen atom or amethyl group; W² is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A² is a divalent linking group and represents a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkylene group in which one or more hydrogenatoms in the alkylene group may be substituted by hydroxy groups or—O—C(═O)—CH₃; Y² is a divalent linking group and represents —O— or —NH—;and n represents an integer of 1 to 3.

[Invention 23]

A display element including the bank according to Invention 22.

[Invention 24]

A fluororesin containing a repeating unit represented by a formula (3-1)and a repeating unit represented by a formula (3-2)

wherein R³⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R³⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R³⁻¹, R³⁻³, and R³⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R³⁻⁵ and R³⁻⁶ each independently represent a hydrogen atom or amethyl group; W³ is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A³⁻¹ and A³⁻² are divalent linking groups and each independentlyrepresent a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylenegroup in which one or more hydrogen atoms in the alkylene group may besubstituted by hydroxy groups or —O—C(═O)—CH₃; Y³⁻¹ and Y³⁻² aredivalent linking groups and each independently represent —O— or —NH—; nrepresents an integer of 1 to 3; and r represents 0 or 1.

[Invention 25]

The fluororesin according to Invention 24, wherein R³⁻³ and R³⁻⁴ eachindependently represent a fluorine atom, a trifluoromethyl group, adifluoromethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethylgroup, an n-heptafluoropropyl group, a 2,2,3,3,3-pentafluoropropylgroup, a 3,3,3-trifluoropropyl group, or a hexafluoroisopropyl group.

[Invention 26]

The fluororesin according to Invention 24 or 25, further containing arepeating unit represented by a formula (3-3):

wherein R³⁻⁷ represents a hydrogen atom or a methyl group; R³⁻⁸represents a C1-C15 linear, C3-C15 branched, or C3-C15 cyclic alkylgroup in which one or more hydrogen atoms in the alkyl group aresubstituted by fluorine atoms; and the repeating unit has a fluorinecontent of 30 mass % or more.

[Invention 27]

The fluororesin according to any one of Inventions 24 to 26, furthercontaining a repeating unit represented by a formula (3-4):

wherein R³⁻⁵, Y³⁻¹, A³⁻¹, and r are the same as R³⁻⁵, Y³⁻¹, A³⁻¹, and rin the formula (3-2), respectively; E³⁻¹ represents a hydroxy group, acarboxy group, or an oxirane group; and s represents 0 or 1.

[Invention 28]

The fluororesin according to any one of inventions 24 to 27, furthercontaining a repeating unit represented by a formula (3-6)

wherein R³⁻⁶ and Y³⁻¹ are the same as R³⁻⁶ and Y³⁻¹ in the formula(3-2), respectively.

[Invention 29]

The fluororesin according to any one of Inventions 24 to 28, furthercontaining a repeating unit represented by a formula (3-5)

wherein R³⁻⁹ represents a hydrogen atom or a methyl group; each B³independently represents a hydroxy group, a carboxy group,—C(═O)—O—R³⁻¹⁰ wherein R³⁻¹⁰ represents a C1-C15 linear, C3-C15branched, or C3-C15 cyclic alkyl group in which one or more hydrogenatoms in the alkyl group are substituted by fluorine atoms, and R³⁻¹⁰has a fluorine content of 30 mass % or more, or —O—C(═O)—R³⁻¹¹ whereinR³⁻¹¹ represents a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup; and m represents an integer of 0 to 3.

[Invention 30]

A photosensitive resin composition at least containing the fluororesinaccording to any one of Inventions 24 to 29; a solvent; and aphotopolymerization initiator.

[Invention 31]

The photosensitive resin composition according to Invention 30, whereinthe solvent is at least one selected from the group consisting of methylethyl ketone, cyclohexanone, methyl isoamyl ketone, 2-heptanone,ethylene glycol, ethylene glycol dimethyl ether, ethylene glycolmonoacetate, diethylene glycol, diethylene glycol monoacetate,diethylene glycol dimethyl ether, propylene glycol, propylene glycolmonoacetate, propylene glycol monomethyl ether (PGME), propylene glycolmonomethyl ether acetate (PGMEA), dipropylene glycol, dipropylene glycolmonoacetate monomethyl ether, dipropylene glycol monoacetate monoethylether, dipropylene glycol monoacetate monopropyl ether, dipropyleneglycol monoacetate monobutyl ether, dipropylene glycol monoacetatemonophenyl ether, 1,4-dioxane, methyl lactate, ethyl lactate, methylacetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethylethoxypropionate, γ-butyrolactone, and hexafluoroisopropyl alcohol.

[Invention 32]

The photosensitive resin composition according to Invention 30 or 31,further containing a crosslinking agent and an alkali-soluble resin.

[Invention 33]

A fluororesin film containing a repeating unit represented by a formula(3-1) and a repeating unit represented by a formula (3-2A):

wherein R³⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R³⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R³⁻¹, R³⁻³, and R³⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R³⁻⁵ and R³⁻⁶ each independently represent a hydrogen atom or amethyl group; W³ is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A³⁻¹ and A³⁻² are divalent linking groups and each independentlyrepresent a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylenegroup in which one or more hydrogen atoms in the alkylene group may besubstituted by hydroxy groups or —O—C(═O)—CH₃; Y³⁻¹ and Y³⁻² aredivalent linking groups and each independently represent —O— or —NH—; nrepresents an integer of 1 to 3; and r represents 0 or 1.

[Invention 34]

A bank containing a repeating unit represented by a formula (3-1) and arepeating unit represented by a formula (3-2A):

wherein R³⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R³⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R³⁻¹, R³⁻³, and R³⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R³⁻⁵ and R³⁻⁶ each independently represent a hydrogen atom or amethyl group; W³ is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A³⁻¹ and A³⁻² are divalent linking groups and each independentlyrepresent a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylenegroup in which one or more hydrogen atoms in the alkylene group may besubstituted by hydroxy groups or —O—C(═O)—CH₃; Y³⁻¹ and Y³⁻² aredivalent linking groups and each independently represent —O— or —NH—; nrepresents an integer of 1 to 3; and r represents 0 or 1.

[Invention 35]

A display element including the bank according to Invention 34.

Advantageous Effects of Invention

The present disclosure can provide a photosensitive resin compositionhaving good liquid repellency.

DESCRIPTION OF EMBODIMENTS

The present disclosure is described in detail below. The followingdescription of structural elements provides exemplary embodiments of thepresent disclosure. The present disclosure is not limited to thesespecific embodiments. Various modifications can be made within the scopeof the gist.

Herein, “[”, “]”, “<”, and “>” in the DESCRIPTION OF EMBODIMENTS aremerely symbols and do not mean anything by themselves.

As used herein, the term “polymer” is a synonym to the term “resin”, andthese terms refer to a high molecular weight compound unless otherwisespecified.

Herein, the term “bank” or “banks” is a synonym to the term “partitionwall” or “partition walls”, and these terms refer to protrusion(s) of apatterned film having recesses and protrusions formed by the inkjetmethod, unless otherwise specified.

Herein, the expression “upper surfaces of the banks” refers to the uppersurfaces (surfaces away from the substrate surface in the verticaldirection) of protrusions of a patterned film having recesses andprotrusions formed by the inkjet method. The expression does notencompass the wall surfaces of the protrusions.

Herein, the expression “resistance to UV-ozone treatment or oxygenplasma treatment” means that the film loss is small, i.e., the filmthickness change is small, before and after UV-ozone treatment or oxygenplasma treatment.

First Embodiment

A photosensitive resin composition according to a first embodiment ofthe present disclosure at least contains a fluororesin having acrosslinking site, a solvent, and a photopolymerization initiator,wherein the fluororesin contains a repeating unit derived from ahydrocarbon having a fluorine atom.

Such a photosensitive resin composition according to the firstembodiment of the present disclosure can be cured at low temperatures,and a cured product of the photosensitive resin composition according tothe first embodiment of the present disclosure has good liquidrepellency.

The photosensitive resin composition according to the first embodimentof the present disclosure can be cured at low temperatures. Thus, whenthe photosensitive resin composition according to the first embodimentof the present disclosure is used to form banks for displays such asorganic EL displays, micro-LED displays, and quantum dot displays, bankscan be formed without causing significant thermal damage on luminescentlayers.

The photosensitive resin composition according to the first embodimentof the present disclosure is preferably cured at a temperature of 140°C. or lower, more preferably at a temperature of 60° C. to 130° C.

A fluororesin cured product obtained by curing the photosensitive resincomposition according to the first embodiment of the present disclosurealso has excellent liquid repellency. Thus, when the photosensitiveresin composition according to the first embodiment of the presentdisclosure is used to form banks for displays such as organic ELdisplays, micro-LED displays, and quantum dot displays, the banks showexcellent ink repellency.

Each constituent of the photosensitive resin composition according tothe first embodiment of the present disclosure is described below.

<Fluororesin>

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the fluororesin contains arepeating unit derived from a hydrocarbon having a fluorine atom, andthe repeating unit preferably has a structure represented by thefollowing formula (1-1), more preferably a structure represented by thefollowing formula (1-2):

[Chem. 15]

—CR¹⁻²═CRf₂  (1-1)

wherein each Rf independently represents a C1-C6 linear, C3-C6 branched,or C3-C6 cyclic perfluoroalkyl group or a fluorine atom; and R¹⁻²represents a hydrogen atom or a C1-C6 linear, C3-C6 branched, or C3-C6cyclic alkyl group.

wherein each Rf independently represents a C1-C6 linear, C3-C6 branched,or C3-C6 cyclic perfluoroalkyl group or a fluorine atom; R¹⁻¹ representsa hydrogen atom, a fluorine atom, or a methyl group; and R¹⁻² representsa hydrogen atom or a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup.

In the formula (1-2), preferably, R¹⁻¹ is a hydrogen atom or a methylgroup. Examples of R¹⁻² include a hydrogen atom, a methyl group, anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a1-methylpropyl group, a 2-methylpropyl group, a tert-butyl group, ann-pentyl group, an isopentyl group, a 1,1-dimethylpropyl group, a1-methylbutyl group, a 1,1-dimethylbutyl group, an n-hexyl group, acyclopentyl group, and a cyclohexyl group. A hydrogen atom, a methylgroup, an ethyl group, an n-propyl group, and an isopropyl group arepreferred. A hydrogen atom and a methyl group are more preferred.

Rf in the formula (1-1) or (1-2) is preferably a fluorine atom, atrifluoromethyl group, a difluoromethyl group, a pentafluoroethyl group,a 2,2,2-trifluoroethyl group, an n-heptafluoropropyl group, a2,2,3,3,3-pentafluoropropyl group, a 3,3,3-trifluoropropyl group, ahexafluoroisopropyl group, a heptafluoroisopropyl group, ann-nonafluorobutyl group, an isononafluorobutyl group, or atert-nonafluorobutyl group; more preferably a fluorine atom, atrifluoromethyl group, a difluoromethyl group, a pentafluoroethyl group,a 2,2,2-trifluoroethyl group, an n-heptafluoropropyl group, a2,2,3,3,3-pentafluoropropyl group, a 3,3,3-trifluoropropyl group, or ahexafluoroisopropyl group; particularly preferably a fluorine atom, adifluoromethyl group, or a trifluoromethyl group.

The following are examples of preferred structures of the repeating unitderived from a hydrocarbon having a fluorine atom in the fluororesin ofthe photosensitive resin composition according to the first embodimentof the present disclosure.

The amount of the repeating unit represented by the formula (1-2) in thefluororesin is preferably 5 mass % or more and 70 mass % or less, morepreferably 10 mass % or more and 50 mass % or less, particularlypreferably 10 mass % or more and 30 mass % or less, relative to 100 mass% of the fluororesin.

When the amount of the repeating unit represented by the formula (1-2)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents. When the amount of the repeating unit represented by theformula (1-2) is less than 5 mass %, the resistance against UV-ozonetreatment or oxygen plasma treatment tends to decrease.

Depending on use, for example, a method in which the fluororesin isdirectly pressed under heat without being dissolved in solvents (i.e., ahot-press method) can be used to form a fluororesin film. In this case,use of the repeating unit represented by the formula (1-2) in an amountof more than 70 mass % does not result in either poor resistance of thewhole fluororesin to UV-ozone treatment or oxygen plasma treatment, orpoor ink repellency after UV-ozone treatment or oxygen plasma treatment,and such use is thus not avoided in the present disclosure.

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the fluororesin may include astructure represented by the following formula (1-3).

In the formula (1-3), R¹⁻³ and R¹⁻⁴ each independently represent ahydrogen atom or a methyl group.

In the formula (1-3), W¹⁻¹ is a divalent linking group and represents—O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or—C(═O)—NH—. Preferred of these are —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, and—C(═O)—NH—.

The fluororesin in which W¹⁻¹ is —O—C(═O)—NH— has better ink repellencyafter UV-ozone treatment or oxygen plasma treatment, and is thus oneparticularly preferred embodiment.

In the formula (1-3), A¹⁻¹ is a divalent linking group and represents aC1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylene group in whichone or more hydrogen atoms in the alkylene group may be substituted byhydroxy groups or —O—C(═O)—CH₃.

When the divalent linking group A¹⁻¹ is a C1-C10 linear alkylene group,examples thereof include a methylene group, an ethylene group, apropylene group, an n-butylene group, an n-pentylene group, ann-hexalene group, an n-heptalene group, an n-octalene group, ann-nonalene group, and an n-decalene group.

When the divalent linking group A¹⁻¹ is a C3-C10 branched alkylenegroup, examples thereof include an isopropylene group, an isobutylenegroup, a sec-butylene group, a tert-butylene group, an isopentalenegroup, and an isohexalen group.

When the divalent linking group A¹⁻¹ is a C3-C10 cyclic alkylene group,examples thereof include two-substituted cyclopropane, two-substitutedcyclobutane, two-substituted cyclopentane, two-substituted cyclohexane,two-substituted cycloheptane, two-substituted cyclooctane,two-substituted cyclodecane, and two-substituted4-tert-butylcyclohexane.

When one or more hydrogen atoms in these alkylene groups are substitutedby hydroxy groups, examples of these hydroxy group-substituted alkylenegroups include a hydroxyethylene group, a 1-hydroxy-n-propylene group, a2-hydroxy-n-propylene group, a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—), a 1-hydroxy-n-butylene group, a 2-hydroxy-n-butylenegroup, a hydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—), ahydroxy-isobutylene group (—CH₂CH(CH₂OH)CH₂—), and ahydroxy-tert-butylene group (—C(CH₂OH)(CH₃)CH₂—).

When one or more hydrogen atoms in these alkylene groups are substitutedby —O—C(═O)—CH₃, examples of these substituted-alkylene groups includethose in which hydroxy groups of the hydroxy group-substituted alkylenegroups exemplified above are substituted by —O—C(═O)—CH₃.

The divalent linking group A¹⁻¹ is preferably a methylene group, anethylene group, a propylene group, an n-butylene group, an isobutylenegroup, a sec-butylene group, a cyclohexyl group, a 2-hydroxy-n-propylenegroup, a hydroxy-isopropylene group (—CH(CH₂OH)CH₂—), a2-hydroxy-n-butylene group, or a hydroxy-sec-butylene group(—CH(CH₂OH)CH₂CH₂—); more preferably an ethylene group, a propylenegroup, a 2-hydroxy-n-propylene group, or a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—); particularly preferably an ethylene group or a2-hydroxy-n-propylene group.

In the formula (1-3), Y¹⁻¹ is a divalent linking group and represents—O— or —NH—, with —O— being more preferred.

In the formula (1-3), n represents an integer of 1 to 3, with n of 1being particularly preferred.

The substituents are each independently in the ortho, meta, or paraposition of the aromatic ring, with the para position being preferred.

The following are examples of preferred structures of the repeating unitrepresented by the formula (1-3). In the examples, the substituentposition in the aromatic ring is the para position. Yet, thesubstituents may be each independently in the ortho or meta position.

The amount of the repeating unit represented by the formula (1-3) in thefluororesin is preferably 5 mass % or more and 70 mass % or less, morepreferably 10 mass % or more and 50 mass % or less, particularlypreferably 10 mass % or more and 30 mass % or less, relative to 100 mass% of the fluororesin.

When the amount of the repeating unit represented by the formula (1-3)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents. When the amount of the repeating unit represented by theformula (1-3) is less than 5 mass %, the resistance against UV-ozonetreatment or oxygen plasma treatment tends to decrease.

Here, it is assumed, although not confirmed, that the repeating unitrepresented by the formula (1-3) according to the first embodiment ofthe present disclosure has an effect of exhibiting resistance toUV-ozone treatment or oxygen plasma treatment. The effects of thepresent disclosure described herein are not intended to be exhaustive.

The fluororesin according to the first embodiment of the presentdisclosure may be, as described above, a mixture (blend) of a copolymercontaining a repeating unit represented by the formula (1-2) and arepeating unit represented by the formula (1-3) and another copolymercontaining a repeating unit represented by the formula (1-2) and arepeating unit represented by the formula (1-3). Specifically, in onepreferred embodiment of the present disclosure, the fluororesinaccording to the first embodiment of the present disclosure is a mixtureof a fluororesin containing a repeating unit represented by the formula(1-3) wherein W¹⁻¹ is —O—C(═O)—NH— and a fluororesin containing arepeating unit represented by the formula (1-3) wherein W¹⁻¹ is—C(═O)—NH—.

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the fluororesin may include astructure represented by the following formula (1-4).

In the formula (1-4), R¹⁻⁵ and R¹⁻⁶ each independently represent ahydrogen atom or a methyl group.

In the formula (1-4), W¹⁻² is a divalent linking group and represents—O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or—C(═O)—NH—. Preferred of these are —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, and—C(═O)—NH—.

The fluororesin according to the first embodiment of the presentdisclosure in which W¹⁻² is —O—C(═O)—NH— has better ink repellency afterUV-ozone treatment or oxygen plasma treatment, and is thus oneparticularly preferred embodiment.

In the formula (1-4), A¹⁻² and A¹⁻³ are divalent linking groups and eachindependently represent a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkylene group in which one or more hydrogen atoms in thealkylene group may be substituted by hydroxy groups or —O—C(═O)—CH₃.

When the divalent linking groups A¹⁻² and A¹⁻³ each independentlyrepresent a C1-C10 linear alkylene group, examples thereof include amethylene group, an ethylene group, a propylene group, an n-butylenegroup, an n-pentylene group, an n-hexalene group, an n-heptalene group,an n-octalene group, an n-nonalene group, and an n-decalene group.

When the divalent linking groups A¹⁻² and A¹⁻³ each independentlyrepresent a C3-C10 branched alkylene group, examples thereof include anisopropylene group, an isobutylene group, a sec-butylene group, atert-butylene group, an isopentalene group, and an isohexalene group.

When the divalent linking groups A¹⁻² and A¹⁻³ each independentlyrepresent a C3-C10 cyclic alkylene group, examples thereof includetwo-substituted cyclopropane, two-substituted cyclobutane,two-substituted cyclopentane, two-substituted cyclohexane,two-substituted cycloheptane, two-substituted cyclooctane,two-substituted cyclodecane, and two-substituted4-tert-butylcyclohexane.

When one or more hydrogen atoms in these alkylene groups are substitutedby hydroxy groups, examples of these hydroxy group-substituted alkylenegroups include a 1-hydroxyethylene group (—CH(OH)CH₂—), a2-hydroxyethylene group (—CH₂CH(OH)—), a 1-hydroxy-n-propylene group, a2-hydroxy-n-propylene group, a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—), a 1-hydroxy-n-butylene group, a 2-hydroxy-n-butylenegroup, a hydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—), ahydroxy-isobutylene group (—CH₂CH(CH₂OH)CH₂—), and ahydroxy-tert-butylene group (—C(CH₂OH)(CH₃)CH₂—).

When one or more hydrogen atoms in these alkylene groups are substitutedby —O—C(═O)—CH₃, examples of these substituted-alkylene groups includethose in which hydroxy groups of the hydroxy group-substituted alkylenegroups exemplified above are substituted by —O—C(═O)—CH₃.

Preferably, the divalent linking groups A¹⁻² and A¹⁻³ each independentlyrepresent a methylene group, an ethylene group, a propylene group, ann-butylene group, an isobutylene group, a sec-butylene group, acyclohexyl group, a 1-hydroxyethylene group (—CH(OH)CH₂—), a2-hydroxyethylene group (—CH₂CH(OH)—), a 2-hydroxy-n-propylene group, ahydroxy-isopropylene group (—CH(CH₂OH)CH₂—), a 2-hydroxy-n-butylenegroup, or a hydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—); morepreferably, an ethylene group, a propylene group, a 1-hydroxyethylenegroup (—CH(OH)CH₂—), a 2-hydroxyethylene group (˜CH₂CH(OH)—), a2-hydroxy-n-propylene group, or a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—); particularly preferably an ethylene group, a1-hydroxyethylene group (—CH(OH)CH₂—), or a 2-hydroxyethylene group(—CH₂CH(OH)—).

In the formula (1-4), Y¹⁻² and Y¹⁻³ are divalent linking groups and eachindependently represent —O— or —NH—, with —O— being preferred.

In the formula (1-4), n represents an integer of 1 to 3, with n of 1being particularly preferred.

In the formula (1-4), r represents 0 or 1. When r is 0, (—C(═O)—)represents a single bond.

The following are examples of preferred structures of the repeating unitrepresented by the formula (1-4).

The amount of the repeating unit represented by the formula (1-4) in thefluororesin is preferably 5 mass % or more and 70 mass % or less, morepreferably 10 mass % or more and 50 mass % or less, particularlypreferably 10 mass % or more and 30 mass % or less, relative to 100 mass% of the fluororesin.

When the amount of the repeating unit represented by the formula (1-4)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents. When the amount of the repeating unit represented by theformula (1-4) is less than 5 mass %, a fluororesin film or banksobtainable from the fluororesin tend to have lower adhesion tosubstrates.

It is assumed, although not confirmed, that the repeating unitrepresented by the formula (1-4) in the fluororesin has an effect ofimproving the adhesion of the resulting fluororesin films or banks tosubstrates. The effects of the present disclosure described herein arenot intended to be exhaustive.

The fluororesin according to the first embodiment of the presentdisclosure may be a mixture (blend) of a copolymer containing arepeating unit represented by the formula (1-2) and a repeating unitrepresented by the formula (1-4) and another copolymer containing arepeating unit represented by the formula (1-2) and a repeating unitrepresented by the formula (1-4). Specifically, in one preferredembodiment of the present disclosure, the fluororesin according to thefirst embodiment of the present disclosure is a mixture of a fluororesincontaining a repeating unit represented by the formula (1-4) whereinW¹⁻² is —O—C(═O)—NH— and a fluororesin containing a repeating unitrepresented by the formula (1-4) wherein W¹⁻² is —C(═O)—NH—.

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the fluororesin may include astructure represented by the following formula (1-5).

In the formula (1-5), R¹⁻⁷ represents a hydrogen atom or a methyl group.

In the formula (1-5), R¹⁻⁸ represents a C1-C15 linear, C3-C15 branched,or C3-C15 cyclic alkyl group in which one or more hydrogen atoms in thealkyl group are substituted by fluorine atoms; and the repeating unithas a fluorine content of 30 mass % or more.

When R¹⁻⁸ is a linear hydrocarbon group, specific examples thereofinclude a methyl group, an ethyl group, a propyl group, a butyl group, apentyl group, a hexyl group, a heptyl group, an octyl group, a nonylgroup, and C10-C14 linear alkyl groups in which one or more hydrogenatoms are substituted by fluorine atoms.

When R¹⁻⁸ is a linear hydrocarbon group, preferably, the repeating unitrepresented by the formula (1-5) is a repeating unit represented by thefollowing formula (1-5-1).

In the formula (1-5-1), R¹⁻⁹ is the same as R¹⁻⁷ in the formula (1-5).

In the formula (1-5-1), X is a hydrogen atom or a fluorine atom.

In the formula (1-5-1), p is an integer of 1 to 4, and q is an integerof 1 to 14. Particularly preferably, p is an integer of 1 or 2, q is aninteger of 2 to 8, and X is a fluorine atom.

The following are examples of preferred structures of the repeating unitrepresented by the formula (1-5).

The amount of the repeating unit represented by the formula (1-5) ispreferably 5 mass % or more and 70 mass % or less, more preferably 10mass % or more and 50 mass % or less, particularly preferably 10 mass %or more and 30 mass % or less, relative to 100 mass % of thefluororesin.

When the amount of the repeating unit represented by the formula (1-5)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents.

The repeating unit represented by the formula (1-5) is a repeating unitthat imparts ink repellency after UV-ozone treatment or oxygen plasmatreatment. Thus, when pursuing high ink repellency, preferably, thefluororesin according to the first embodiment of the present disclosurecontains the repeating unit represented by the formula (1-5).

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the fluororesin may include astructure represented by the following formula (1-6).

In the formula (1-6), R¹⁻¹⁰ represents a hydrogen atom or a methylgroup.

In the formula (1-6), each B¹ independently represents a hydroxy group,a carboxy group, —C(═O)—O—R¹⁻¹¹ (R¹⁻¹¹ represents a C1-C15 linear,C3-C15 branched, or C3-C15 cyclic alkyl group in which one or morehydrogen atoms in the alkyl group are substituted by fluorine atoms, andR¹⁻¹¹ has a fluorine content of 30 mass % or more), or —O—C(═O)—R¹⁻¹²(R¹⁻¹² represents a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup); and m represents an integer of 0 to 3.

The following are examples of preferred structures of the repeating unitrepresented by the formula (1-6).

The amount of the repeating unit represented by the formula (1-6) ispreferably 5 mass % or more and 70 mass % or less, more preferably 10mass % or more and 50 mass % or less, particularly preferably 20 mass %or more and 40 mass % or less, relative to 100 mass % of thefluororesin.

When the amount of the repeating unit represented by the formula (1-6)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents.

A repeating unit represented by the formula (1-6) wherein B¹ is ahydroxy group or a carboxy group has solubility in an alkali developer.Thus, when it is desired to impart alkali developability to a filmobtainable from the fluororesin, preferably, the fluororesin accordingto the first embodiment of the present disclosure contains the repeatingunit represented by the formula (1-6) wherein B¹⁻¹ is a hydroxy group ora carboxy group.

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the fluororesin may include astructure represented by the following formula (1-7).

In the formula (1-7), R¹⁻¹³ represents a hydrogen atom or a methylgroup.

In the formula (1-7), A¹⁻⁴ is a divalent linking group and represents aC1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylene group in whichone or more hydrogen atoms in the alkylene group may be substituted byhydroxy groups or —O—C(═O)—CH₃.

When the divalent linking group A¹⁻⁴ is a C1-C10 linear alkylene group,examples thereof include a methylene group, an ethylene group, apropylene group, an n-butylene group, an n-pentylene group, ann-hexalene group, an n-heptalene group, an n-octalene group, ann-nonalene group, and an n-decalene group.

When the divalent linking group A¹⁻⁴ is a C3-C10 branched alkylenegroup, examples thereof include an isopropylene group, an isobutylenegroup, a sec-butylene group, a tert-butylene group, an isopentalenegroup, and an isohexalene group.

When the divalent linking group A¹⁻⁴ is a C3-C10 cyclic alkylene group,examples thereof include two-substituted cyclopropane, two-substitutedcyclobutane, two-substituted cyclopentane, two-substituted cyclohexane,two-substituted cycloheptane, two-substituted cyclooctane,two-substituted cyclodecane, and two-substituted4-tert-butylcyclohexane.

When one or more hydrogen atoms in these alkylene groups are substitutedby hydroxy groups, examples of these hydroxy group-substituted alkylenegroups include a 1-hydroxyethylene group (—CH(OH)CH₂—), a2-hydroxyethylene group (—CH₂CH(OH)—), a 1-hydroxy-n-propylene group, a2-hydroxy-n-propylene group, a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—), a 1-hydroxy-n-butylene group, a 2-hydroxy-n-butylenegroup, a hydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—), ahydroxy-isobutylene group (—CH₂CH(CH₂OH)CH₂—), and ahydroxy-tert-butylene group (—C(CH₂OH)(CH₃)CH₂—).

When one or more hydrogen atoms in these alkylene groups are substitutedby —O—C(═O)—CH₃, examples of these substituted-alkylene groups includethose in which hydroxy groups of the hydroxy group-substituted alkylenegroups exemplified above are substituted by —O—C(═O)—CH₃.

The divalent linking group A¹⁻⁴ is preferably a methylene group, anethylene group, a propylene group, an n-butylene group, an isobutylenegroup, a sec-butylene group, a cyclohexyl group, a 1-hydroxyethylenegroup (—CH(OH)CH₂—), a 2-hydroxyethylene group (—CH₂CH(OH)—), a2-hydroxy-n-propylene group, a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—), a 2-hydroxy-n-butylene group, or ahydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—); more preferably anethylene group, a propylene group, a 1-hydroxyethylene group(—CH(OH)CH₂—), a 2-hydroxyethylene group (—CH₂CH(OH)—), a2-hydroxy-n-propylene group, or a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—); particularly preferably an ethylene group, a1-hydroxyethylene group (—CH(OH)CH₂—), or a 2-hydroxyethylene group(—CH₂CH(OH)—).

In the formula (1-7), Y¹⁻⁴ is a divalent linking group and represents—O— or —NH—, with —O— being more preferred.

In the formula (1-7), r represents 0 or 1. When r is 0, (—C(═O)—)represents a single bond.

In the formula (1-7), E¹⁻¹ represents a hydroxy group, a carboxy group,or an oxirane group.

When E¹⁻¹ is an oxirane group, examples thereof include an ethyleneoxide group, a 1,2-propylene oxide group, and a 1,3-propylene oxidegroup. Preferred of these is an ethylene oxide group.

In the formula (1-7), s represents 0 or 1. When s is 0, (—Y¹⁻⁴-A¹⁻⁴-)represents a single bond. When r is 0 and s is 0, the structure has E¹⁻¹bonded to the main chain of the repeating unit.

The following are examples of preferred structures of the repeating unitrepresented by the formula (1-7).

A repeating unit represented by the formula (1-7) wherein E¹⁻¹ is ahydroxy group or a carboxy group imparts solubility to the fluororesinin an alkali developer. Thus, when it is desired to impart alkalidevelopability to a film obtainable from the fluororesin, preferably,the fluororesin according to the first embodiment of the presentdisclosure contains the repeating unit represented by the formula (1-7)wherein E¹⁻¹ is a hydroxy group or a carboxy group.

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the molecular weight of thefluororesin in terms of weight average molecular weight measured by gelpermeation chromatography (GPC) using polystyrene as a standardsubstance is preferably 1000 or more and 1000000 or less, morepreferably 2000 or more and 500000 or less, particularly preferably 3000or more and 100000 or less. When the molecular weight is less than 1000,the resulting fluororesin film or banks for organic EL tend to have alow strength. When the molecular weight is more than 1000000, it may bedifficult to form a fluororesin film due to lack of solubility of thefluororesin in solvents.

The dispersity (Mw/Mn) is preferably 1.01 to 5.00, more preferably 1.01to 4.00, particularly preferably 1.01 to 3.00.

The fluororesin may be a random copolymer, an alternating copolymer, ablock copolymer, or a graft copolymer. Preferably, the fluororesin is arandom copolymer to suitably (not locally) disperse characteristics ofeach repeating unit.

The following are preferred embodiments of the fluororesin in thephotosensitive resin composition according to the first embodiment ofthe present disclosure.

Embodiment 1-1

Fluororesin containing a repeating unit represented by the followingformula (1-2) and a repeating unit represented by the following formula(1-3)Formula (1-2): R¹⁻¹ and R¹⁻² are hydrogen atoms, and each Rf isindependently a fluorine atom, a difluoromethyl group, or atrifluoromethyl group.Formula (1-3): R¹⁻³ and R¹⁻⁴ are hydrogen atoms; W¹ is a —O—C(═O)—NH—,—C(═O)—O—C(═O)—NH—, or —C(═O)—NH—; A¹⁻¹ is an ethylene group; Y¹⁻¹ is—O—; and n is 1.

Embodiment 1-2

Fluororesin containing a repeating unit represented by the followingformula (1-2) and a repeating unit represented by the following formula(1-3)Formula (1-2): same as described in Embodiment 1-1Formula (1-3): R¹⁻³ and R¹⁻⁴ are hydrogen atoms; W¹⁻¹ is —O—; A¹⁻¹ is a2-hydroxy-n-propylene group or a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—); Y¹⁻¹ is —O—; and n is 1.

Embodiment 1-3

Fluororesin containing repeating units represented by the followingformulas (1-2), (1-3), and (1-5-1)Formula (1-2): same as described in Embodiment 1-1Formula (1-3): same as described in Embodiment 1-1Formula (1-5-1): R¹⁻⁹ is a methyl group; p is an integer of 2; q is aninteger of 4 to 8; and X is a fluorine atom.

Embodiment 1-4

Fluororesin containing repeating units represented by the followingformulas (1-2), (1-3), (1-5-1), and (1-6)Formula (1-2): same as described in Embodiment 1-1Formula (1-3): same as described in Embodiment 1-1Formula (1-5-1): same as described in Embodiment 1-3Formula (1-6): R¹⁻¹⁰ is a hydrogen atom; B¹ is a hydroxy group or acarboxy group; and m is 1.

Embodiment 1-5

Fluororesin containing a repeating unit represented by the followingformula (1-2) and a repeating unit represented by the following formula(1-4)Formula (1-2): same as described in Embodiment 1-1Formula (1-4): R¹⁻⁵ and R¹⁻⁶ are each independently a hydrogen atom or amethyl group; W¹⁻² is —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A¹⁻² and A¹⁻³ are each independently an ethylene group; Y¹⁻² and Y¹⁻³are —O—; n is 1; and r is 1.

Embodiment 1-6

Fluororesin containing a repeating unit represented by the followingformula (1-2) and a repeating unit represented by the following formula(1-4)Formula (1-2): same as described in Embodiment 1-1Formula (1-4): R¹⁻⁵ and R¹⁻⁶ are each independently a hydrogen atom or amethyl group; W¹⁻² is —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A¹⁻² and A¹⁻³ are each independently an ethylene group, a1-hydroxy-n-ethylene group (—CH(OH)CH₂—), or a 2-hydroxy-n-ethylenegroup (—CH₂CH(OH)—); Y¹⁻² and Y¹⁻³ are —O—; n is 1; and r is 1.

Embodiment 1-7

Fluororesin containing a repeating unit represented by the followingformula (1-2) and a repeating unit represented by the following formula(1-4)Formula (1-2): same as described in Embodiment 1-1Formula (1-4): R¹⁻⁵ and R¹⁻⁶ are each independently a hydrogen atom or amethyl group; W¹⁻² is —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A¹⁻² and A¹⁻³ are each independently an ethylene group or a butyl group;Y¹⁻² and Y¹⁻³ are —O—; n is 1; and r is 0.

Embodiment 1-8

Fluororesin containing repeating units represented by the followingformulas (1-2), (1-4), and (1-5-1)Formula (1-2): same as described in Embodiment 1-1Formula (1-4): same as described in Embodiment 1-5Formula (1-5-1): same as described in Embodiment 1-3

Embodiment 1-9

Fluororesin containing repeating units represented by the followingformulas (1-2), (1-4), (1-5-1), and (1-7)Formula (1-2): same as described in Embodiment 1-1Formula (1-4): same as described in Embodiment 1-5Formula (1-5-1): same as described in Embodiment 1-3Formula (1-7): R¹⁻¹³ is a hydrogen atom; A¹⁻⁴ is an ethylene group; Y¹⁻⁴is —O—; r is 1; s is 1; and E¹⁻¹ is a hydroxy group or a carboxy group.

Embodiment 1-10

Fluororesin containing repeating units represented by the followingformulas (1-2), (1-4), (1-5-1), (1-6), and (1-7)Formula (1-2): same as described in Embodiment 1-1Formula (1-4): same as described in Embodiment 1-5Formula (1-5-1): same as described in Embodiment 1-3Formula (1-6): same as described in Embodiment 1-4Formula (1-7): same as described in Embodiment 1-9

In the photosensitive resin composition according to the firstembodiment of the present disclosure, the fluororesin has a fluorinecontent of preferably 20 to 50 mass %, more preferably 25 to 40 mass %.

The fluororesin having a fluorine content in the above ranges is easilysoluble in solvents. A fluororesin film or banks having excellent liquidrepellency can be obtained because the fluororesin contains fluorineatoms.

Herein, the fluorine content of the fluororesin can be calculated fromproperties measured by nuclear magnetic resonance (NMR) spectroscopysuch as molar percentages of monomers constituting the fluororesin,molecular weights of monomers constituting the fluororesin, and amountof fluorine in each monomer.

The following describes a fluorine content measurement method, providingthat the fluororesin is a resin derived from1,1-bistrifluoromethylbutadiene, 4-hydroxystyrene, and2-(perfluorohexyl)ethyl methacrylate.

(i) First, the fluororesin is measured by NMR to calculate thepercentage of each monomer (mol percentage).

(ii) The molecular weight (Mw) of the monomer of the fluororesin ismultiplied by the mol percentage, and the resulting values are added upto determine the total value. The weight percentage (wt %) of eachmonomer is calculated from the total value.

The molecular weight of 1,1-bistrifluoromethylbutadiene is 190, themolecular weight of 1,1-bistrifluoromethylbutadiene is 120, and themolecular weight of 2-(perfluorohexyl)ethyl methacrylate is 432.

(iii) Next, the fluorine content of the monomer containing fluorine iscalculated.

(iv) For each monomer, “fluorine content in the monomer÷molecular weight(Mw) of the monomer×weight percentage (wt %)” is calculated, and theresulting values are added up.

(v) The value obtained in (iv) above is divided by the total valueobtained in (ii) above to calculate the fluorine content of thefluororesin.

<Solvent>

In the photosensitive resin composition according to the firstembodiment of the present disclosure, any solvent that can dissolve thefluororesin may be used, and examples thereof include ketones, alcohols,polyhydric alcohols and their derivatives, ethers, esters, aromaticsolvents, and fluorine solvents. These may be used alone or incombination of two or more thereof.

Specific examples of the ketones include acetone, methyl ethyl ketone,cyclopentanone, cyclohexanone, methyl isoamyl ketone, 2-heptanone,cyclopentanone, methyl isobutyl ketone, methyl isopentyl ketone, and2-heptanone.

Specific examples of the alcohols include isopropanol, butanol,isobutanol, n-pentanol, isopentanol, tert-pentanol, 4-methyl-2-pentanol,3-methyl-3-pentanol, 2,3-dimethyl-2-pentanol, n-hexanol, n-heptanol,2-heptanol, n-octanol, n-decanol, s-amyl alcohol, t-amyl alcohol,isoamyl alcohol, 2-ethyl-1-butanol, lauryl alcohol, hexyl decanol, andoleyl alcohol.

Specific examples of the polyhydric alcohols and their derivativesinclude ethylene glycol, ethylene glycol monoacetate, ethylene glycoldimethyl ether, diethylene glycol, diethylene glycol dimethyl ether,diethylene glycol monoacetate, propylene glycol, propylene glycolmonoacetate, propylene glycol monomethyl ether (PGME), propylene glycolmonoethyl ether, propylene glycol monopropyl ether, propylene glycolmonobutyl ether, propylene glycol monomethyl ether acetate (PGMEA), andmonomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether,and monophenyl ether of dipropylene glycol or dipropylene glycolmonoacetate.

Specific examples of the ethers include diethyl ether, diisopropylether, tetrahydrofuran, dioxane, and anisole.

Specific examples of the esters include methyl lactate, ethyl lactate(EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate,ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate, andγ-butyrolactone.

Examples of the aromatic solvents include xylene and toluene.

Examples of the fluorine solvents include chlorofluorocarbons,hydrochlorofluorocarbons, perfluoro compounds, and hexafluoroisopropylalcohol.

Other solvents such as terpene-based petroleum naphtha solvents andparaffinic solvents, which are high-boiling-point weak solvents, canalso be used to improve coating properties.

Of these, preferably, the solvent is at least one selected from thegroup consisting of methyl ethyl ketone, cyclohexanone, methyl isoamylketone, 2-heptanone, ethylene glycol, ethylene glycol dimethyl ether,ethylene glycol monoacetate, diethylene glycol, diethylene glycolmonoacetate, diethylene glycol dimethyl ether, propylene glycol,propylene glycol monoacetate, propylene glycol monomethyl ether (PGME),propylene glycol monomethyl ether acetate (PGMEA), dipropylene glycol,dipropylene glycol monoacetate monomethyl ether, dipropylene glycolmonoacetate monoethyl ether, dipropylene glycol monoacetate monopropylether, dipropylene glycol monoacetate monobutyl ether, dipropyleneglycol monoacetate monophenyl ether, 1,4-dioxane, methyl lactate, ethyllactate, methyl acetate, ethyl acetate, butyl acetate, methylmethoxypropionate, ethyl ethoxypropionate, γ-butyrolactone, andhexafluoroisopropyl alcohol. More preferred are methyl ethyl ketone,propylene glycol monomethyl ether acetate (PGMEA), propylene glycolmonomethyl ether (PGME), cyclohexanone, ethyl lactate, butyl acetate,and γ-butyrolactone.

The amount of the solvent in the photosensitive resin compositionaccording to the first embodiment of the present disclosure ispreferably 50 parts by mass or more and 2000 parts by mass or less, morepreferably 100 parts by mass or more and 1000 parts by mass or less,relative to the concentration (100 parts by mass) of the fluororesin(when the photosensitive resin composition contains the later-describedalkali-soluble resin, the concentration is the sum including thealkali-soluble resin). The thickness of the resulting resin film can beadjusted by adjusting the amount of the solvent. When the amount is inthe above ranges, the resulting resin film has a thickness particularlysuitable to obtain banks for organic EL.

<Photopolymerization Initiator>

In the photosensitive resin composition according to the firstembodiment of the present disclosure, any known photopolymerizationinitiator can be used as long as it polymerizes a monomer having apolymerizable double bond by high energy rays such as electromagneticwaves or electron beams.

The photopolymerization initiator can be a photo-radical initiator or aphotoacid initiator. These may be used alone or in combination with aphoto-radical initiator and a photoacid initiator. Two or morephoto-radical initiators or photoacid initiators may be mixed. Use ofthe photopolymerization initiator in combination with additives enablesliving polymerization in some cases. Known additives can be used.

Specifically, the photo-radical initiators can be classified into thefollowing types, for example: the intramolecular cleavage type thatcleaves the intermolecular bond by absorption of electromagnetic wavesor electron beams to generate radicals; and the hydrogen extraction typethat, when used in combination with a hydrogen donor such as a tertiaryamine or ether, generates radicals. Either type can be used. Aphoto-radical initiator of a type different from those described abovecan also be used.

Specific examples of the photo-radical initiators includebenzophenone-based, acetophenone-based, diketone-based, acylphosphineoxide-based, quinone-based, and acyloin-based photo-radical initiators.

Specific examples of the benzophenone-based photo-radical initiatorsinclude benzophenone, 4-hydroxybenzophenone, 2-benzoylbenzoic acid,4-benzoylbenzoic acid, 4,4′-bis(dimethylamino)benzophenone, and4,4′-bis(diethylamino)benzophenone. Preferred of these are2-benzoylbenzoic acid, 4-benzoylbenzoic acid, and4,4′-bis(diethylamino)benzophenone.

Specific examples of the acetophenone-based photo-radical initiatorsinclude acetophenone, 2-(4-toluenesulfonyloxy)-2-phenylacetophenone,p-dimethylaminoacetophenone, 2,2′-dimethoxy-2-phenylacetophenone,p-methoxyacetophenone,2-methyl-[4-(methylthio)phenyl]-2-morphorino-1-propanone, and2-benzyl-2-dimethylamino-1-(4-morphorinophenyl)-butan-1-one. Preferredof these are p-dimethylaminoacetophenone and p-methoxyacetophenone.

Specific examples of the diketone-based photo-radical initiators include4,4′-dimethoxybenzyl, methyl benzoylformate, and9,10-phenanthrenequinone. Preferred of these are 4,4′-dimethoxybenzyland methyl benzoylformate.

Specific examples of the acylphosphine oxide-based photo-radicalinitiators include bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide.

Specific examples of the quinone-based photo-radical initiators includeanthraquinone, 2-ethylanthraquinone, camphorquinone, and1,4-naphthoquinone. Preferred of these are camphorquinone and1,4-naphthoquinone.

Specific examples of the acyloin-based photo-radical initiators includebenzoin, benzoin methyl ether, benzoin ethyl ether, and benzoinisopropyl ether. Preferred of these are benzoin and benzoin methylether.

Preferred are benzophenone-based, acetophenone-based, and diketone-basedphoto-radical initiators. More preferred are benzophenone-basedphoto-radical initiators.

Examples of preferred commercially available photo-radical initiatorsinclude Irgacure 127, Irgacure 184, Irgacure 369, Irgacure 651, Irgacure819, Irgacure 907, Irgacure 2959, Irgacure OXE-01, Darocur 1173, andLucirin TPO (trade names) available from BASF. More preferred of theseare Irgacure 651 and Irgacure 369.

Specifically, the photoacid initiator is an onium salt of a pair ofcation and anion, the cation being at least one selected from the groupconsisting of aromatic sulfonic acid, aromatic iodonium, aromaticdiazonium, aromatic ammonium, thianthrenium, thioxanthonium, and(2,4-cyclopentadien-1-yl) (1-methylethylbenzene)-iron, the anion beingat least one selected from the group consisting of tetrafluoroborate,hexafluorophosphate, hexafluoroantimonate, and pentafluorophenyl borate.

Particularly preferred of these arebis[4-(diphenylsulfonio)phenyl]sulfide bishexafluorophosphate,bis[4-(diphenylsulfonio)phenyl]sulfidetetrakis(pentafluorophenyl)borate, and diphenyliodoniumhexafluorophosphate.

Examples of commercially available photoacid generators includeCPI-100P, CPI-110P, CPI-101A, CPI-200K, and CPI-210S (trade names)available from San-Apro Ltd.; CYRACURE Photoinitiator UVI-6990, CYRACUREPhotoinitiator UVI-6992, and CYRACURE Photoinitiator UVI-6976 (tradenames) available from Dow Chemical Japan Limited; ADECA OPTOMER SP-150,ADECA OPTOMER SP-152, ADECA OPTOMER SP-170, ADECA OPTOMER SP-172, andADECA OPTOMER SP-300 (trade names) available from ADEKA; CI-5102 andCI-2855 (trade names) available from Nippon Soda Co., Ltd.; SAN AIDSI-60L, SAN AID SI-80L, SAN AID SI-100L, SAN AID SI-110L, SAN AIDSI-180L, SAN AID SI-110, and SAN AID SI-180 (trade names) available fromSanshin Chemical Industry Co. Ltd; Esacure 1064 and Esacure 1187 (tradenames) available from Lamberti; and Irgacure 250 (trade name) availablefrom Ciba Specialty Chemicals.

The amount of the photopolymerization initiator in the photosensitiveresin composition according to the first embodiment of the presentdisclosure is preferably 0.1 parts by mass or more and 30 parts by massor less, more preferably 1 part by mass or more and 20 parts by mass orless, relative to 100 parts by mass of the fluororesin (when thephotosensitive resin composition contains the later-describedalkali-soluble resin, the concentration is the sum including thealkali-soluble resin). When the amount of the photopolymerizationinitiator is less than 0.1 parts by mass, the crosslinking effect tendsto be insufficient. When the amount thereof is more than 30 parts bymass, the resolution and sensitivity tend to be low.

The photosensitive resin composition according to the first embodimentof the present disclosure essentially contains a fluororesin, a solvent,and a photopolymerization initiator, and may further contain acrosslinking agent, an alkali-soluble resin, a naphthoquinonediazidegroup-containing compound, a basic compound, and other additives.

<Crosslinking Agent>

The crosslinking agent reacts with a repeating unit represented by theformula (1-3) or (1-4), whereby the resin can have a crosslinkedstructure. This can improve the mechanical strength of the resultingfilm.

A known crosslinking agent can be used. Specific examples thereofinclude compounds obtained by reacting an amino group-containingcompound such as melamine, acetoguanamine, benzoguanamine, urea,ethylene urea, propylene urea, or glycoluril with formaldehyde orformaldehyde and a lower alcohol, and substituting a hydrogen atom ofthe amino group by a hydroxymethyl group or a lower alkoxymethyl group;polyfunctional epoxy compounds; polyfunctional oxetane compounds;polyfunctional isocyanate compounds; and polyfunctional acrylatecompounds. Here, those that use melamine are referred to asmelamine-based crosslinking agents, those that use urea are referred toas urea-based crosslinking agents, those that use alkylene urea suchethylene urea or propylene urea are referred to as alkylene urea-basedcrosslinking agents, and those that use glycoluril are referred to asglycoluril-based crosslinking agents. These crosslinking agents may beused alone or in combination of two or more thereof.

Preferably, the crosslinking agent is at least one selected from thesecrosslinking agents. Particularly preferred are glycoluril-basedcrosslinking agents and polyfunctional acrylate compounds.

Examples of the melamine-based crosslinking agents includehexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethylmelamine, and hexabutoxybutyl melamine. Preferred of these ishexamethoxymethyl melamine.

Examples of the urea-based crosslinking agents includebismethoxymethylurea, bisethoxymethylurea, bispropoxymethylurea, andbisbutoxymethylurea. Preferred of these is bismethoxymethylurea.

Examples of the alkylene urea-based crosslinking agents include ethyleneurea-based crosslinking agents such as mono- and/or di-hydroxymethylatedethylene urea, mono- and/or di-methoxymethylated ethylene urea, mono-and/or di-ethoxymethylated ethylene urea, mono- and/ordi-propoxymethylated ethylene urea, and mono- and/or di-butoxymethylatedethylene urea; propylene urea-based crosslinking agents such as mono-and/or di-hydroxymethylated propylene urea, mono- and/ordi-methoxymethylated propylene urea, mono- and/or di-ethoxymethylatedpropylene urea, mono- and/or di-propoxymethylated propylene urea, andmono- and/or di-butoxymethylated propylene urea;1,3-di(methoxymethyl)-4,5-dihydroxy-2-imidazolidinone; and1,3-di(methoxymethyl)-4,5-dimethoxy-2-imidazolidinone.

Examples of the glycoluril-based crosslinking agents include mono-, di-,tri-, and/or tetra-hydroxymethylated glycoluril; mono-, di-, tri-,and/or tetra-methoxymethylated glycoluril; mono-, di-, tri-, and/ortetra-ethoxymethylated glycoluril; mono-, di-, tri-, and/ortetra-propoxymethylated glycoluril; and mono-, di-, tri-, and/ortetra-butoxymethylated glycoluril.

Examples of the polyfunctional acrylate compounds include polyfunctionalacrylates (e.g., A-TMM-3, A-TMM-3L, A-TMM-3LM-N, A-TMPT, and AD-TMP(trade names) available from Shin-Nakamura Chemical Co., Ltd.);polyethylene glycol diacrylates (e.g., A-200, A-400, and A-600 (tradenames) available from Shin-Nakamura Chemical Co., Ltd.); urethaneacrylates (e.g., UA-122P, UA-4HA, UA-6HA, UA-6LPA, UA-11003H, UA-53H,UA-4200, UA-200PA, UA-33H, UA-7100, and UA-7200 (trade names) availablefrom Shin-Nakamura Chemical Co., Ltd.); and pentaerythritoltetraacrylate.

The following are examples of preferred polyfunctional acrylatecompounds.

The amount of the crosslinking agent in the photosensitive resincomposition according to the first embodiment of the present disclosureis preferably 10 parts by mass or more and 300 parts by mass or less,more preferably 50 parts by mass or more and 200 parts by mass or less,relative to 100 parts by mass of the fluororesin (when thephotosensitive resin composition contains the later-describedalkali-soluble resin, the concentration is the sum including thealkali-soluble resin). When the amount of the crosslinking agent is lessthan 10 parts by mass, the crosslinking effect tends to be insufficient.When the amount thereof is more than 300 parts by mass, the resolutionand sensitivity tend to be low.

<Alkali-Soluble Resin>

When the photosensitive resin composition according to the firstembodiment of the present disclosure contains an alkali-soluble resin,it is possible to improve the shape of banks obtainable from thephotosensitive resin composition according to the first embodiment ofthe present disclosure.

Examples of the alkali-soluble resin include alkali-soluble novolacresins.

Alkali-soluble novolac resins can be obtained by condensation of phenolwith aldehyde in the presence of an acid catalyst.

Specific examples of the phenol include phenol, o-cresol, m-cresol,p-cresol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol,3,4-dimethylphenol, 3,5-dimethylphenol, 2,3,5-trimethylphenol,3,4,5-trimethylphenol, resorcinol, 2-methylresorcinol,4-ethylresorcinol, hydroquinone, methylhydroquinone, catechol,4-methyl-catechol, pyrogallol, phloroglucinol, thymol, and isothymol.These phenols may be used alone or in combination of two or morethereof.

Specific examples of the aldehyde include formaldehyde, trioxane,paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde,phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde,o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde,o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde,nitrobenzaldehyde, furfural, glyoxal, glutaraldehyde,terephthalaldehyde, and isophthalaldehyde.

Specific examples of the acid catalyst include hydrochloric acid, nitricacid, sulfuric acid, phosphoric acid, phosphorous acid, formic acid,oxalic acid, acetic acid, methanesulfonic acid, diethyl sulfate, andp-toluenesulfonic acid. These acid catalysts may be used alone or incombination of two or more thereof.

Other examples of the alkali-soluble resin include acid-modified epoxyacrylic resins. Examples of commercially available acid-modified epoxyacrylic resins include CCR-1218H, CCR-1159H, CCR-1222H, CCR-1291H,CCR-1235, PCR-1050, TCR-1335H, UXE-3024, ZAR-1035, ZAR-2001H, ZFR-1185,and ZCR-1569H (trade names) available from Nippon Kayaku Co., Ltd.

The weight average molecular weight of the alkali-soluble resin ispreferably 1000 to 50000 in terms of developability and resolution ofthe photosensitive resin composition.

The amount of the alkali-soluble resin in the photosensitive resincomposition according to the first embodiment of the present disclosureis preferably 500 parts by mass or more and 10000 parts by mass or less,more preferably 1000 parts by mass or more and 7000 parts by mass orless, relative to 100 parts by mass of the fluororesin. When the amountof the alkali-soluble resin is more than 10000 parts by mass, thefluororesin according to the first embodiment of the present disclosuretends to have insufficient ink repellency after UV-ozone treatment oroxygen plasma treatment.

<Naphthoquinonediazide Group-Containing Compound>

When the photosensitive resin composition according to the firstembodiment of the present disclosure contains a naphthoquinonediazidegroup-containing compound, it is possible to improve the shape of banksobtainable from the photosensitive resin composition according to thefirst embodiment of the present disclosure.

Any naphthoquinonediazide group-containing compound can be used, and onecommonly used as a photosensitive component of a resist composition fori-rays can be used.

Specific examples of the naphthoquinonediazide group-containing compoundinclude a naphthoquinone-1,2-diazide-4-sulfonate compound, anaphthoquinone-1,2-diazide-5-sulfonate compound, anaphthoquinone-1,2-diazide-6-sulfonate compound, anaphthoquinone-1,2-diazide sulfonate compound, anorthobenzoquinonediazide sulfonate compound, and anorthoanthraquinonediazide sulfonate compound. Preferred of these are anaphthoquinone-1,2-diazide-4-sulfonate compound, anaphthoquinone-1,2-diazide-5-sulfonate compound, and anaphthoquinone-1,2-diazide-6-sulfonate compound, because they haveexcellent solubility. These compounds may be used alone or incombination of two or more thereof.

The amount of the naphthoquinonediazide group-containing compound in thephotosensitive resin composition according to the first embodiment ofthe present disclosure is preferably 10 parts by mass to 60 parts bymass, more preferably 20 parts by mass to 50 parts by mass, relative to100 parts by mass of the fluororesin (when the photosensitive resincomposition contains the above-described alkali-soluble resin, theconcentration is the sum including the alkali-soluble resin). When theamount thereof is more than 60 parts by weight, the photosensitive resincomposition tends to lack sensitivity.

<Basic Compound>

The basic compound functions to decrease the diffusion rate of an acidgenerated by the photoacid generator when the acid is diffused into afilm of the photosensitive resin composition according to the firstembodiment of the present disclosure.

The presence of the basic compound makes it possible to adjust the aciddiffusion distance and improve the shape of banks.

The presence of the basic compound also makes it possible to stably formbanks with desired accuracy because the banks are less likely to bedeformed even when the banks formed are left to stand for a long timebefore being exposed.

Examples of the basic compound include aliphatic amines, aromaticamines, heterocyclic amines, and aliphatic polycyclic amines. Preferredof these are aliphatic amines. Specific examples thereof includesecondary or tertiary aliphatic amines and alkyl alcohol amines. Thesebasic compounds may be used alone or in combination of two or morethereof.

Examples of the aliphatic amines include alkylamines and alkyl alcoholamines each in which at least one hydrogen atom of ammonia (NH₃) issubstituted by a C12 or lower alkyl group or a hydroxyalkyl group.Specific examples thereof include trimethylamine, triethylamine,tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine,tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine,tri-n-decanylamine, tri-n-dodecylamine, dimethylamine, diethylamine,di-n-propylamine, di-n-butylamine, di-n-pentylamine, di-n-hexylamine,di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decanylamine,di-n-dodecylamine, dicyclohexylamine, methylamine, ethylamine,n-propylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine,n-octylamine, n-nonylamine, n-decanylamine, n-dodecylamine,diethanolamine, triethanolamine, diisopropanolamine,triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine.

Preferred of these are dialkylamine, trialkylamine, and alkyl alcoholamines. More preferred are alkyl alcohol amines. Particularly preferredof these alkyl alcohol amines are triethanolamine andtriisopropanolamine.

Examples of the aromatic amines and heterocyclic amines include anilineand aniline derivatives such as N-methylaniline, N-ethylaniline,N-propylaniline, N,N-dimethylaniline, 2-methylaniline, 3-methylaniline,4-methylaniline, ethylaniline, propylaniline, trimethylaniline,2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline,2,6-dinitroaniline, 3,5-dinitroaniline, and N,N-dimethyltoluidine;heterocyclic amines such as 1,5-diazabicyclo[4.3.0]non-5-en,1,8-diazabicyclo[5.4.0]undec-7-en, 1,4-diazabicyclo[2.2.2]octane,pyridine, bipyridine, 4-dimethylaminopyridine, hexamethylenetetramine,and 4,4-dimethylimidazoline; hindered amines such asbis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate; alcoholicnitrogen-containing compounds such as 2-hydroxypyridine, aminocresol,2,4-quinolinediol, 3-indolemethanol hydrate, monoethanolamine,diethanolamine, triethanolamine, N-ethyldiethanolamine,N,N-diethylethanolamine, triisopropanolamine, 2,2′-iminodiethanol,2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol,4-(2-hydroxyethyl)morpholine, 2-(2-hydroxyethyl)pyridine,1-(2-hydroxyethyl)piperazine, and1-[2-(2-hydroxyethoxy)ethyl]piperazine; and picoline, lutidine, pyrrole,piperidine, piperazine, indole, hexamethylenetetramine, and the like

The amount of the basic compound in the photosensitive resin compositionaccording to the first embodiment of the present disclosure ispreferably 0.001 parts by mass to 2 parts by mass, more preferably 0.01parts by mass to 1 part by mass, relative to 100 parts by mass of thefluororesin (when the photosensitive resin composition contains theabove-described alkali-soluble resin, the concentration is the sumincluding the alkali-soluble resin). When the amount of the basiccompound is less than 0.001 parts by mass, the effect thereof as anadditive tends to be insufficient. When the amount thereof is more than2 parts by mass, the resolution and sensitivity tend to be low.

<Other Additives>

The photosensitive resin composition according to the first embodimentof the present disclosure may contain other additives if necessary.Examples of the other additives include various additives such asdissolution inhibitors, plasticizers, stabilizers, colorants,surfactants, thickeners, leveling agents, defoamers, compatibilityagents, adhesives, and antioxidants.

These other additives may be known ones.

Preferably, the surfactant contains any one or more of fluorine-basedsurfactants and silicone-based surfactants (fluorine-based surfactants,silicone-based surfactants, and surfactants containing both fluorineatoms and silicon atoms).

Described below is a method of producing a fluororesin cured productusing the photosensitive resin composition according to the firstembodiment of the present disclosure.

The method of producing a fluororesin cured product according to thefirst embodiment of the present disclosure includes a baking step ofbaking the photosensitive resin composition according to the firstembodiment of the present disclosure at a temperature of 140° C. orlower for curing.

In this step, preferably, the photosensitive resin composition accordingto the first embodiment of the present disclosure is baked at 60° C. to130° C.

The method of producing a fluororesin cured product according to thefirst embodiment of the present disclosure may include an exposing stepof exposing the photosensitive resin composition to high energy raysbefore the baking step.

Preferably, the high energy rays are at least one type of rays selectedfrom the group consisting of ultraviolet rays, gamma rays, X-rays, andα-rays.

The fluororesin cured product obtained as described above has excellentwater repellency and oil repellency owing to its low surface freeenergy. For example, the fluororesin cured product can be used as awater- and oil-repellent agent for treating fabrics (base materials) forclothes or the like, or a sealing agent for protecting substrates (basematerials) for microfabricated semiconductors. The fluororesin curedproduct can be used as a material to protect base materials in variousapplications.

The method of producing a fluororesin cured product according to thefirst embodiment of the present disclosure may include the followingsteps: (1-1) a film forming step, (1-2) an exposing step, (1-3) adeveloping step, and (1-4) a baking step.

Each step is described below.

(1-1) Film Forming Step

First, the photosensitive resin composition according to the firstembodiment of the present disclosure is applied to a substrate, and thenheated, whereby the photosensitive resin composition is formed into afluororesin film.

The heating conditions are not limited, but preferably, the heating isperformed at 80° C. to 100° C. for 60 to 200 seconds.

This can remove the solvents and the like in the photosensitive resincomposition.

The substrate may be a silicon wafer, metal, glass, ITO substrate, orthe like.

The substrate may include an organic or inorganic film formed thereon inadvance. For example, the substrate may include an underlayer such as ananti-reflective film or a multilayer resist, and the underlayer may havea pattern formed thereon. The substrate may be pre-washed. For example,the substrate may be washed with ultrapure water, acetone, an alcohol(methanol, ethanol, or isopropyl alcohol), or the like.

A known method such as spin coating can be used to apply thephotosensitive resin composition according to the first embodiment ofthe present disclosure to the substrate.

(1-2) Exposing Step

Next, a desired photo mask is set in an exposure device, and thefluororesin film is exposed to high energy rays through the photo mask.

Preferably, the high energy rays are at least one type of rays selectedfrom the group consisting of ultraviolet rays, gamma rays, X-rays, andα-rays.

The exposure of the high energy rays is preferably 1 mJ/cm² or more and200 mJ/cm² or less, more preferably 10 mJ/cm² or more and 100 mJ/cm² orless.

(1-3) Developing Step

Next, the fluororesin film after the exposing step is developed with analkaline aqueous solution to obtain a patterned fluororesin film.

Specifically, the exposed or non-exposed portions of the fluororesinfilm are dissolved in an alkaline aqueous solution to obtain a patternedfluororesin film.

The alkaline aqueous solution may be, for example, a tetramethylammoniumhydroxide (TMAH) aqueous solution, a tetrabutylammonium hydroxide (TBAH)aqueous solution, or the like.

When the alkaline aqueous solution is a tetramethylammonium hydroxide(TMAH) aqueous solution, the concentration thereof is preferably 0.1mass % or more and 5 mass % or less, more preferably 2 mass % or moreand 3 mass % or less.

Any known development method, such as dipping, paddling, or spraying,can be used.

The development time (contact time of the developer with the fluororesinfilm) is preferably 10 seconds or more and 3 minutes or less, morepreferably 30 seconds or more and 2 minutes or less.

After development, a step of washing the patterned fluororesin film withdeionized water or the like may be included if necessary. Regarding thewashing method and washing time, washing for 10 seconds or more and 3minutes or less is preferred, and washing for 30 seconds or more and 2minutes or less is more preferred.

(1-4) Baking Step

After the developing step, the patterned fluororesin film is baked at atemperature of 140° C. or lower for curing, whereby a fluororesin curedproduct is obtained.

The baking can be performed on a hot plate. Preferably, the bakingconditions are 60° C. to 130° C. for 10 to 120 minutes.

The fluororesin cured product produced as described above can be used asbanks for displays such as organic EL displays, micro-LED displays, andquantum dot displays.

In other words, the method of producing a fluororesin cured productaccording to the first embodiment of the present disclosure can alsoproduce banks for displays such as organic EL displays, micro-LEDdisplays, and quantum dot displays.

The method of producing a fluororesin cured product according to thefirst embodiment of the present disclosure can cure a photosensitiveresin composition at low temperatures. Thus, the method of producing afluororesin cured product according to the first embodiment of thepresent disclosure can produce banks for displays such as organic ELdisplays, micro-LED displays, and quantum dot displays, without causingsignificant thermal damage on luminescent layers.

In the method of producing a fluororesin cured product according to thefirst embodiment of the present disclosure, UV-ozone treatment or oxygenplasma treatment may be performed after the baking step (1-4). Of these,UV-ozone treatment is preferred.

With this treatment, residual organic matter in recesses of thepatterned fluororesin film can be removed, and uneven wetting of the inkdropped is reduced. This can prevent defects in display elements.

Examples According to the First Embodiment

The first embodiment of the present disclosure is described in detailbelow with reference to examples but the present disclosure is notlimited to these examples.

1. Synthesis of Monomers [Synthesis Example 1-1] Synthesis of1,1-bistrifluoromethylbutadiene (BTFBE)

A 1000-ml glass flask equipped with a stirrer was charged withconcentrated sulfuric acid (400 g) and heated to 100° C. Then,1,1,1-trifluoro-2-trifluoromethyl-4-penten-2-ol (300 g) was graduallydropped thereto over one hour. After dropping, the mixture was stirredat 100° C. for 60 minutes. No residual raw materials were detected by¹⁹F-NMR analysis of the reaction solution. Then, a fraction at 68° C. to70° C. was collected by atmospheric distillation from the reactionsolution, whereby 1,1-bistrifluoromethylbutadiene (hereinafter describedas BTFBE) was obtained (yield: 58%).

Presumably, the following chemical reaction occurred in this reaction.

<Results of NMR Analysis>

The following results were obtained by NMR analysis of the BTFBEsynthesized.

¹H-NMR (solvent: deuterated chloroform; standard substance: TMS); δ(ppm) 5.95 (1H, dd) 6.05 (1H, dd), 6.85 (1H, m), 7.04 (1H, m)

¹⁹F-NMR (solvent: deuterated chloroform; standard substance: C₆D₆); δ(ppm) −65.3 (3F, m), −58.4 (3F, m)

[Synthesis Example 1-2] Synthesis of 4-hydroxystyrene (p-HO-St)

A 1000-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with p-acetoxystyrene (a product of TokyoChemical Industry Co., Ltd., hereinafter described as p-AcO-St) (100 g)and methanol (300 g), which were mixed therein, and1,3,5-trihydroxybenzene (0.50 g; equivalent to 0.5 mass % of p-AcO-St)as a polymerization inhibitor was added to the mixture. Then, after thesolution was cooled to 0° C. in an ice bath, a sodium hydroxide aqueoussolution having a concentration of 12 mass % (corresponding to 1.0equivalent of p-AcO-St) was gradually dropped over 40 minutes, followedby stirring at 0° C. for 30 minutes. No residual raw materials weredetected by ¹H-NMR analysis of the reaction solution. Then, ahydrochloric acid aqueous solution having a concentration of 18 mass %(corresponding to 0.8 equivalents of p-AcO-St) was dropped over 30minutes, followed by stirring for 30 minutes. The pH of the solution wasmeasured to be 6.

The resulting reaction solution was subjected to extraction withmethyl-t-butylether (360 g) at room temperature (about 20° C.), followedby washing twice with purified water (330 g). To the resulting organiclayer was added 1,3,5-trihydroxybenzene in an amount equivalent to 1mass % of 4-hydroxystyrene. Subsequently, 4-hydroxystyrene wasconcentrated to 72 mass %, and added to n-octane (a poor solvent) cooledto 0° C. Then, the solution was placed in an ice bath and stirred forone hour to precipitate crystals of 4-hydroxystyrene. The crystals werefiltered and further washed with n-octane. Then, the crystals werevacuum dried at 25° C. Thus, white crystals of 4-hydroxystyrene(hereinafter described as p-HO-St) were obtained (yield: 66%).

Presumably, the following chemical reaction occurred in this reaction.

2. Production of Fluororesin (First Step: Polymerization) [Measurementof Molar Ratio of Repeating Units] NMR

The molar ratio of the repeating units of the polymer was determinedfrom the measurements of ¹H-NMR, ¹⁹F-NMR, or ¹³C-NMR.

[Measurement of Polymer Molecular Weight] GPC

The weight average molecular weight Mw and the molecular weightdispersity (Mw/Mn: ratio of the weight average molecular weight Mw tothe number average molecular weight Mn) of the polymer were measured bya high-speed gel permeation chromatograph (hereinafter sometimesreferred to as GPC; model: HLC-8320 GPC available from TosohCorporation) with an ALPHA-M column and an ALPHA-2500 column (bothavailable from Tosoh Corporation) connected in series, usingtetrahydrofuran (THF) as a developing solvent and polystyrene as astandard substance. A refractive index difference detector was used.

2-1. Polymerization of Fluororesin Precursors [Synthesis of FluororesinPrecursor 1-1]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with BTFBE obtained in Synthesis Example 1-1(9.5 g (0.05 mol)), 2-hydroxyethyl methacrylate (a product of TokyoChemical Industry Co., Ltd., hereinafter described as HEMA) (13.1 g(0.10 mol)), 2-(perfluorohexyl)ethyl methacrylate (a product of TokyoChemical Industry Co., Ltd., hereinafter described as MA-C6F) (43.2 g(0.1 mol)), p-HO-St obtained in Synthesis Example 1-2 (9.0 g (0.075mol)), and MEK (70 g). Then, 2,2′-azobis(2-methylbutyronitrile) (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asAIBN) (1.6 g (0.005 mol)) was added thereto, followed by degassing withstirring. Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 75° C. for reaction for sixhours. n-Heptane (380 g) was dropped into the reaction system, whereby atransparent viscous substance was precipitated. This viscous substancewas isolated by decantation. Vacuum drying was performed at 60° C. Thus,a fluororesin precursor 1-1 as a transparent viscous substance wasobtained (67 g; yield: 90%).

<Results of NMR Measurement>

The fluororesin precursor 1-1 was subjected to NMR analysis. The ratio(molar ratio) of “Repeating units of the fluororesin precursor 1-1”below was as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:p-HO-St repeating unit=20:28:30:22.

Repeating Units of the Fluororesin Precursor 1-1

<Results of GPC Measurement>

The fluororesin precursor 1-1 was subjected to GPC measurement. As aresult, Mw was 6700, and Mw/Mn was 1.3.

[Synthesis of Fluororesin Precursor 1-2]

The same procedure as in the synthesis of the fluororesin precursor 1-1was performed, except that p-HO-St was replaced by vinyl benzoic acid (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asVBA) Thus, a fluororesin precursor 1-2 containing the followingrepeating units was obtained (yield: 91%).

<Results of NMR Measurement>

The fluororesin precursor 1-2 was subjected to NMR analysis. The ratio(molar ratio) of “Repeating units of fluororesin precursor 1-2” belowwas as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:VBA repeating unit=19:27:31:23.

Repeating Units of Fluororesin Precursor 1-2

<Results of GPC Measurement>

The fluororesin precursor 1-2 was subjected to GPC measurement. As aresult, Mw was 6900, and Mw/Mn was 1.3.

[Synthesis of Fluororesin Precursor 1-3]

The same procedure as in the synthesis of the fluororesin precursor 1-1was performed, except that p-HO-St was replaced by p-acetoxystyrene (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asp-AcO-St). Thus, a fluororesin precursor 1-3 containing the followingrepeating units was obtained (yield: 88%).

<Results of NMR Measurement>

The fluororesin precursor 1-3 was subjected to NMR analysis. The ratio(molar ratio) of “Repeating units of fluororesin precursor 1-3” belowwas as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:p-AcO-St repeating unit=15:33:30:22.

Repeating Units of Fluororesin Precursor 1-3

<Results of GPC Measurement>

The fluororesin precursor 1-3 was subjected to GPC measurement. As aresult, Mw was 7100, and Mw/Mn was 1.3.

[Synthesis of Fluororesin Precursor 1-4]

The same procedure as in the synthesis of the fluororesin precursor 1-1was performed, except that p-HO-St was replaced by styrene (a product ofTokyo Chemical Industry Co., Ltd., hereinafter described as St). Thus, afluororesin precursor 1-4 containing the following repeating units wasobtained (yield: 90%).

<Results of NMR Measurement>

The fluororesin precursor 1-4 was subjected to NMR analysis. The ratio(molar ratio) of “Repeating units of fluororesin precursor 1-4” belowwas as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:St repeating unit=16:34:29:21.

Repeating Units of Fluororesin Precursor 1-4

<Results of GPC Measurement>

The fluororesin precursor 1-4 was subjected to GPC measurement. As aresult, Mw was 7400, and Mw/Mn was 1.3.

[Synthesis of Fluororesin Precursor 1-5]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature with HEMA (13.01 g (0.1 mol)), MA-C6F (43.2 g (0.1 mol)),hexafluoro-2-propyl methacrylate (HFIP-M) (23.6 g (0.1 mol)), methylmethacrylate (MAA) (8.66 g (0.1 mol)), and MEK (88 g). Then, AIBN (1.6 g(0.010 mol)) was added thereto, followed by degassing with stirring.Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 80° C., followed by reactionfor six hours. The reaction solution after the reaction was dropped inton-heptane (530 g), whereby a white precipitate was obtained. Theprecipitate was filtered and vacuum dried at 60° C., whereby afluororesin precursor 5 as a white solid was obtained (60 g; yield:66%).

<Results of NMR Measurement>

The fluororesin precursor 1-5 was subjected to NMR analysis. The ratio(molar ratio) of “Repeating units of fluororesin precursor 1-5” belowwas as follows: HEMA repeating unit:MA-C6F repeating unit:HFIP-Mrepeating unit:MAA repeating unit=25:25:24:26.

Repeating Units of Fluororesin Precursor 1-5

<Results of GPC Measurement>

The fluororesin precursor 1-5 was subjected to GPC measurement. As aresult, Mw was 10300, and Mw/Mn was 1.4.

[Synthesis of Fluororesin Precursor 1-6]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with HEMA (13.1 g (0.10 mol)), MA-C6F (43.2 g(0.10 mol)), VBA (11.1 g (0.075 mol)), and MEK (75 g). Then,2,2′-azobis(2-methylbutyronitrile) (a product of Tokyo Chemical IndustryCo., Ltd., hereinafter described as AIBN) (1.6 g (0.005 mol)) was addedthereto, followed by degassing with stirring. Subsequently, the flaskwas purged with nitrogen gas, and the temperature inside the flask wasraised to 75° C. for reaction for six hours. n-Heptane (400 g) wasdropped into the reaction system, whereby a transparent viscoussubstance was precipitated. This viscous substance was isolated bydecantation. Vacuum drying was performed at 60° C. Thus, a fluororesinprecursor 1-6 as a transparent viscous substance was obtained (56 g:yield: 83%).

<Results of NMR Measurement>

The fluororesin precursor 1-6 was subjected to NMR analysis. The ratio(molar ratio) of “Repeating units of fluororesin precursor 1-6” belowwas as follows: HEMA repeating unit:MA-C6F repeating unit:VBA repeatingunit=33:32:35.

Repeating Units of Fluororesin Precursor 1-6

<Results of GPC Measurement>

The fluororesin precursor 1-6 was subjected to GPC measurement. As aresult, Mw was 14300, and Mw/Mn was 1.6.

2-2. Synthesis of Comparative Fluororesin Precursor ComparativePolymerization Example 1-1

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with HEMA (13.1 g (0.10 mol)), MA-C6F (43.2 g(0.1 mol)), normal-butyl methacrylate (hereinafter abbreviated asMA-nBu) (14.2 g (0.1 mol)), and MEK (71 g). Then, AIBN (0.8 g (0.005mol)) was added thereto, followed by degassing with stirring.Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 80° C., followed by reactionfor six hours. The reaction solution after the reaction was dropped inton-heptane (500 g), whereby a white precipitate was obtained. Theprecipitate was filtered and vacuum dried at 60° C., whereby acomparative fluororesin precursor 1-1 as a white solid was obtained(49.3 g; yield: 70%).

<Results of NMR Measurement>

The comparative fluororesin precursor 1-1 was subjected to NMR analysis.The ratio (molar ratio) of “Repeating units of comparative fluororesinprecursor 1-1” below was as follows: HEMA repeating unit:MA-C6Frepeating unit:MA-nBu repeating unit=35:32:33.

Repeating Units of Comparative Fluororesin Precursor 1-1

<Results of GPC Measurement>

The comparative fluororesin precursor 1-1 was subjected to GPCmeasurement. As a result, Mw was 10700, and Mw/Mn was 1.7.

Comparative Polymerization Example 1-2

The same procedure as in the synthesis of the comparative fluororesinprecursor 1-1 was performed, except that MA-nBu was replaced byp-AcO-St. Thus, a comparative fluororesin precursor 1-2 containing thefollowing repeating units was obtained (yield: 74%).

<Results of NMR Measurement>

The comparative fluororesin precursor 1-2 was subjected to NMR analysis.The ratio (molar ratio) of “Repeating units of comparative fluororesinprecursor 1-2” was as follows: HEMA repeating unit:MA-C6F repeatingunit:p-AcO-St repeating unit=33:34:33.

Repeating Units of Comparative Fluororesin Precursor 1-2

<Results of GPC Measurement>

The comparative fluororesin precursor 1-2 was subjected to GPCmeasurement. As a result, Mw was 15300, and Mw/Mn was 1.7.

Comparative Polymerization Example 1-3

The same procedure as in the synthesis of the comparative fluororesinprecursor 1-1 was performed, except that MA-nBu was replaced by p-HO-St.Thus, a comparative fluororesin precursor 1-3 containing the followingrepeating units was obtained (yield: 75%).

<Results of NMR Measurement>

The comparative fluororesin precursor 1-3 was subjected to NMR analysis.The ratio (molar ratio) of “Repeating units of comparative fluororesinprecursor 1-3” was as follows: HEMA repeating unit:MA-C6F repeatingunit:p-HO-St repeating unit=34:32:34.

Repeating Units of Comparative Fluororesin Precursor 1-13

<Results of GPC Measurement>

The comparative fluororesin precursor 1-3 was subjected to GPCmeasurement. As a result, Mw was 12300, and Mw/Mn was 1.6.

Table 1-1 shows the repeating units of the resulting fluororesinprecursors and comparative fluororesin precursors, molar ratio of therepeating units, and weight average molecular weight (Mw), molecularweight distribution (Mw/Mn), yield, and fluorine content (%) of each ofthe fluororesin precursors and comparative fluororesin precursors. Thefluorine content was determined by calculating the weight ratio of therepeating units from the molar ratio after polymerization of themonomers and calculating the weight percentage of fluorine atomsconstituting the monomers.

TABLE 1-1 Composition (repeating units) Fluorine (molar ratio) Molecularweight content Polymer 1-1 1-2 1-3 1-4 Mw Mw/Mn Yield (%) (%)Fluororesin BTFBE HEMA MA-C6F p-HO-St 6,700 1.3 90 42 precursor 1-1 2028 30 22 Fluororesin BTFBE HEMA MA-C6F VBA 6,900 1.3 91 41 precursor 1-219 27 31 23 Fluororesin BTFBE HEMA MA-C6F p-AcO-St 7,100 1.3 88 38.5precursor 1-3 15 33 30 22 Fluororesin BTFBE HEMA MA-C6F St 7,400 1.3 9040 precursor 1-4 16 34 29 21 Fluororesin — HEMA MA-C6F MAA 10,300 1.4 6638 precursor 1-5 26 33 54 HFIP-M 16 Fluororesin — HEMA MA-C6F VBA 14,3001.6 83 34 precursor 1-6 33 32 35 Comparative — HEMA MA-C6F MA-nBu 10,7001.7 70 34 fluororesin 35 32 33 precursor 1-1 Comparative — HEMA MA-C6Fp-AcO-St 15,300 1.7 74 34.5 fluororesin 33 34 33 precursor 1-2Comparative — HEMA MA-C6F p-HO-St 12,300 1.6 75 36.5 fluororesin 34 3234 precursor 1-3

3. Production of Fluororesin (Second Step: Addition Reaction)

The fluororesin precursors and comparative fluororesin precursorsobtained in “2. Production of fluororesin (first step: polymerization)”were each reacted with an acrylic acid derivative, whereby fluororesinswere synthesized. The acrylic acid derivative was 2-isocyanatoethylacrylate (trade name: KarenzAOI, a product of Showa Denko K.K.)represented by the following formula. This reaction is an additionreaction of hydroxy groups of each fluororesin precursor and the acrylicacid derivative.

Described below are fluororesin synthesis examples. The resultingfluororesins were named as follows.

The first number represents the number of the fluororesin precursor. Thesubsequent alphabet letter represents the acrylic acid derivative used.KarenzAOI is represented by “A”. The last number in the parenthesisindicates the nominal amount of acrylic acid derivative introduced(molar ratio) relative to the resin precursor.

[Synthesis of Fluororesin 1-1-A (100)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 1-1 (10 g (hydroxy equivalent: 0.0115 mol)) andPGMEA (30 g). Then, KarenzAOI (1.62 g (0.0114 mol)) was added thereto,and a reaction was carried out at 45° C. for eight hours. Aftercompletion of the reaction, the reaction solution was concentrated, andn-heptane (150 g) was then added to obtain a precipitate. Theprecipitate was filtered and vacuum dried at 35° C., whereby afluororesin 1-1-A (100) as a white solid was obtained (11.1 g; yield:95%).

<Results of NMR Measurement>

In the fluororesin 1-1-A (100), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 99:1. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 1-1 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W² in the formula (4)) was“—O—C(═O)—NH—”.

[Synthesis of Fluororesins 1-2-A (100) to 1-6-A (100) and ComparativeFluororesins 1-1-A (100) to 1-3-A (100)]

Fluororesins 1-2-A (100) to 1-6A (100) and comparative fluororesins1-1-A (100) to 1-3-A (100) were synthesized as in the fluororesin 1-1-A(100). Table 1-2 shows the fluororesin precursors used, ratio of acrylicacid derivative introduced, crosslinking group structure formed (W¹⁻² inthe formula (1-4)), amount of crosslinking groups introduced (reactionrate), amount of residual hydroxy groups (non-reaction rate), weightaverage molecular weight (Mw), and molecular weight distribution(Mw/Mn).

TABLE 1-2 Ratio of acrylic acid derivative introduced (molar ratio)Amount of acrylic acid Amount of residual Fluorine Fluororesin Formedbond derivative introduced hydroxy groups (non- Molecular weight contentFluororesin No. precursor No. (W¹⁻² in formula (1-4)) (reaction rate %)reaction rate %) Mw Mw/Mn (%) 1-1-A (100) 1-1 —O—C(═O)—NH— 99 1 8,2001.3 36 1-2-A (100) 1-2 —O—C(═O)—NH— 98 2 8,400 1.3 35 1-3-A (100) 1-3—O—C(═O)—NH— 99 1 8,600 1.3 32 1-4-A (100) 1-4 —O—C(═O)—NH— 98 2 9,0001.3 33 1-5-A (100) 1-5 —O—C(═O)—NH— 98 2 12,100 1.4 34 1-6-A (100) 1-6—O—C(═O)—NH— 97 3 16,200 1.7 28 Comparative 1-1-A (100) Comparative 1-1—O—C(═O)—NH— 98 2 12,600 1.8 28 Comparative 1-2-A (100) Comparative 1-2—O—C(═O)—NH— 99 1 18,200 1.7 29 Comparative 1-3-A (100) Comparative 1-3—O—C(═O)—NH— 98 2 14,300 1.7 31

4. Evaluation of Low-Temperature Curing of Each Cured Fluororesin Film[Formation of Photocurable Fluororesin Compositions 1-1 to 1-6 andComparative Photocurable Fluororesin Compositions 1-1 to 1-3]

The fluororesins and comparative fluororesins produced (10 parts, each)were each mixed with a solvent (75 parts), a photopolymerizationinitiator (5 parts), and a crosslinking agent (10 parts), and theresulting solutions were filtered through a 0.2-μm membrane filter,whereby curable fluororesin compositions 1-1 to 1-6 and comparativecurable fluororesin compositions 1-1 to 1-3 were prepared.

The following solvent, photopolymerization initiator, and crosslinkingagent were used.

Solvent: propylene glycol monomethyl ether acetate (PGMEA)Photopolymerization initiator: Irgacure 369 (available from BASF)Crosslinking agent: pentaerythritol tetraacrylate (available from TokyoChemical Industry Co., Ltd.)

[Formation of Fluororesin Films 1-1 to 1-6 and Comparative FluororesinFilms 1-1 to 1-3]

The curable fluororesin compositions 1-1 to 1-6 and comparative curablefluororesin compositions 1-1 to 1-3 prepared were each applied to asilicon wafer using a spin coater at a rotation speed of 1000 rpm.Subsequently, each curable fluororesin composition was heated on a hotplate at 90° C. for 150 seconds to remove the solvent, wherebyfluororesin films 1-1 to 1-6 and comparative fluororesin films 1-1 to1-3 were each formed on the silicon wafer.

[Evaluation of Cured Fluororesin Film by Low-Temperature Curing Method]

The resulting resin films were each entirely exposed (200 mJ/cm²) toi-rays (wavelength: 365 nm) using a mask aligner (available from SUSSMicroTec Group) without a mask.

The films after exposure were subjected to comparison between a method(i) of forming a cured fluororesin film by curing at high temperatures(a method of heating at 230° C. for one hour) and the following methods(ii) to (iv) of forming a cured fluororesin film by curing at lowtemperatures.

(ii): Method of heating at 90° C. for one hour(iii): Method of heating at 90° C. for one hour after the resin film isentirely exposed to i-rays (wavelength: 365 nm) for additional exposure(2000 mJ/cm²) using the mask aligner without a mask(iv): Method of heating at 90° C. for one hour after the resin film isentirely exposed to UV-ozone for five minutes using a UV-ozone treatmentdevice (available from Sen Lights Corporation; model number: L17-110)

Each cured fluororesin film was evaluated for degree of curing by thedegree of temporal change in contact angle with respect to anisole (asolvent for quantum dot color filters) at 1 second and 10 seconds afterdropping of anisole.

After the thickness of the cured fluororesin film was measured inadvance, a silicon substrate having the cured film on its surface wasimmersed in anisole in a petri dish, and heated on a hot plate at 140°C. for 10 minutes. Subsequently, anisole on the surface of the curedfilm was sufficiently removed by an air gun, and the thickness wasmeasured again. The cured film was evaluated by film thickness changebefore and after immersion in anisole.

The cured fluororesin film obtained by the method (i) of curing at hightemperatures was used as reference. Cured fluororesin films withcomparable evaluation results were determined as “good”, and the restwere determined as “poor”. Specifically, less temporal change in contactangle with respect to anisole is better, and less film thickness changeafter immersion in anisole is better.

[Contact Angle Measurement]

With a contact angle meter “DMs-601” available from Kyowa InterfaceScience Co., Ltd., each cured fluororesin film surface and eachcomparative cured fluororesin film surface were subjected to contactangle measurement with respect to anisole.

[Film Thickness Measurement]

Using a stylus-type surface shape measuring instrument “Dektak-8”available from Bruker Nano, the thickness of each cured fluororesin filmand the thickness of each comparative cured fluororesin film weremeasured before and after immersion in anisole.

Table 1-3 shows the results.

TABLE 1-3 Curing method (i) (Reference example) (ii) (iii) (iv) CuredContact angle Film thickness Contact angle Film thickness Contact angleFilm thickness Contact angle Film thickness fluororesin (°) (nm) (°)(nm) (°) (nm) (°) (nm) film 1 s 10 s Before After 1 s 10 s Before After1 s 10 s Before After 1 s 10 s Before After 1-1 61.0 60.8 1210 1210 61.048.5 1230 870 60.5 47.8 1200 810 61.2 61.2 1250 1250 1-2 70.0 69.8 11901190 65.0 64.5 1210 1200 66.0 65.6 1190 1190 70.1 69.8 1230 1220 1-366.1 65.8 1200 1200 57.0 38.0 1230 840 57.0 38.0 1250 830 66.0 65.9 11801170 1-4 66.2 66.0 1230 1220 63.1 42.7 1250 650 64.5 41.7 1230 650 67.267.0 1200 1190 1-5 60.1 59.9 1180 1170 65.0 63.5 1270 1250 64.2 63.61230 1230 60.0 59.8 1230 1230 1-6 67.1 67.0 1160 1160 63.1 62.3 12501240 63.5 62.8 1200 1190 66.3 66.3 1180 1170 Comparative 61.3 61.0 11801170 65.0 34.3 1160 320 63.2 33.1 1230 300 35.2 20.2 1050 320 1-1Comparative 64.5 63.8 1190 1180 67.2 43.1 1150 410 65.2 41.8 1210 42032.1 18.6 1080 380 1-2 Comparative 62.5 62.1 1160 1160 68.1 45.3 1190330 67.2 45.4 1190 350 28.3 13.9 1120 280 1-3

According to the results, the cured fluororesin films 1-1 to 1-6 formedby the method (iv) were comparable to those of the cured fluororesinfilms obtained by the method (i) (reference). This confirmed sufficientcuring even at low temperatures.

Regarding the cured fluororesin films formed by the methods (ii) and(iii), the cured fluororesin films 1-2, 1-5, and 1-6 showed goodresults.

In contrast, the comparative cured fluororesin films 1-1 to 1-3 werepoor with a significant temporal decrease in contact angle with respectto anisole and a significant decrease in film thickness after immersionin anisole, as compared to the cured fluororesin films formed by themethod (i) (reference). Anisole after being used for immersion wasconcentrated by an evaporator and the resulting oily matter wasanalyzed, with the result that each fluororesin was detected. Thisconfirmed that these fluororesins were dissolved in anisole due toinsufficient curing.

5. Preparation of Photosensitive Resin Compositions [Preparation ofPhotosensitive Resin Compositions 1-1 to 1-10 and ComparativePhotosensitive Resin Compositions 1-1 to 1-6]

The fluororesins or comparative fluororesins produced above, solvents,photopolymerization initiators, crosslinking agents, and alkali-solubleresins were blended according to Table 1-4. The resulting solutions werefiltered through a 0.2-μm membrane filter, whereby photosensitive resincompositions 1 to 10 and comparative photosensitive resin compositions 1to 6 were prepared.

The following solvents, photopolymerization initiators, crosslinkingagents, and alkali-soluble resins were used.

Solvents:

S-1: propylene glycol monomethyl ether acetate (PGMEA); S-2:γ-butyrolactone; S-3: propylene glycol monomethyl ether (PGME); S-4:methyl ethyl ketone; S-5: ethyl lactate

Photopolymerization Initiators:

Ini-1: 4-benzoylbenzoic acid; Ini-2: Irgacure 651 (available from BASF);Ini-3: Irgacure 369 (available from BASF)

Crosslinking Agents:

CL-1: pentaerythritol tetraacrylate (available from Tokyo ChemicalIndustry Co., Ltd.); CL-2: A-TMM-3 (available from Shin-NakamuraChemical Co., Ltd.)

Alkali-Soluble Resins:

ASP-1: CCR-1235 (available from Nippon Kayaku Co., Ltd.)ASP-2: ZCR-1569H (available from Nippon Kayaku Co., Ltd.)

[Table 1-4]

TABLE 1-4 Photosensitive Photopolymerization resin Fuororesin Solventinitiator Crosslinking agent Alkali-soluble resin composition Parts byParts by Parts by Parts by Parts by No. Type mass Type mass Type massType mass Type mass 1-1 1-1-A (100) 1.0 S-1 70 Ini-2 1.5 CL-1 10 ASP-110 S-3 30 1-2 1-1-A (100) 1.0 S-1 70 Ini-2 1.5 CL-2 10 ASP-2 10 S-2 301-3 1-2-A (100) 1.0 S-1 65 Ini-1 1.5 CL-1 10 ASP-1 10 S-3 35 1-4 1-2-A(100) 1.0 S-1 65 Ini-2 1.5 CL-2 10 ASP-2 10 S-4 35 1-5 1-3-A (100) 1.0S-1 70 Ini-2 1.5 CL-1 10 ASP-1 10 S-3 30 1-6 1-3-A (100) 1.0 S-1 65Ini-3 1.5 CL-2 10 ASP-2 10 S-5 35 1-7 1-4-A (100) 1.0 S-1 65 Ini-2 1.5CL-1 10 ASP-1 10 S-3 35 1-8 1-4-A (100) 1.0 S-3 70 Ini-3 1.5 CL-2 10ASP-2 10 S-5 30 1-9 1-5-A (100) 1.0 S-1 65 Ini-2 1.5 CL-1 10 ASP-2 10S-3 35  1-10 1-6-A (100) 1.0 S-1 70 Ini-2 1.5 CL-2 10 ASP-2 10 S-3 30Comparative Comparative 1.0 S-1 70 Ini-2 1.5 CL-1 10 ASP-1 10 1-1 1-1-A(100) S-3 30 Comparative Comparative 1.0 S-1 55 Ini-3 1.5 CL-2 10 ASP-210 1-2 1-1-A (100) S-3 45 Comparative Comparative 1.0 S-1 70 Ini-3 1.5CL-1 10 ASP-1 10 1-3 1-2-A (100) S-3 30 Comparative Comparative 1.0 S-160 Ini-1 1.5 CL-1 10 ASP-2 10 1-4 1-2-A (100) S-3 40 ComparativeComparative 1.0 S-1 65 Ini-2 1.5 CL-1 10 ASP-1 10 1-5 1-3-A (100) S-3 35Comparative Comparative 1.0 S-1 60 Ini-2 1.5 CL-1 10 ASP-1 10 1-6 1-3-A(100) S-3 40

6. Evaluation of Low-Temperature Curing of Each Photosensitive ResinComposition

The photosensitive resin compositions 1-1 to 1-10 and the comparativephotosensitive resin compositions 1-1 to 1-6 prepared in “5. Preparationof photosensitive resin compositions” were each applied to a siliconwafer using a spin coater at a rotation speed of 1000 rpm as in “4.Evaluation of low-temperature curing of each fluororesin film”.Subsequently, these resin compositions were heated on a hot plate at 90°C. for 150 seconds, whereby photosensitive resin films 1-1 to 1-10 andcomparative photosensitive resin films 1-1 to 1-6 (the numberscorrespond to the respective numbers of the photosensitive resincompositions) were each formed on the silicon wafer.

[Evaluation of Cured Fluororesin Film by Low-Temperature Curing Method]

The resulting resin films were each entirely exposed (200 mJ/cm²) toi-rays (wavelength: 365 nm) using the mask aligner without a mask.

The films after exposure were subjected to comparison between curedfluororesin films formed by the method (i) and cured fluororesin filmsformed by the methods (ii) to (iv) as in “4. Evaluation oflow-temperature curing of each fluororesin film”.

Each cured fluororesin film was evaluated for degree of curing as in “4.Evaluation of low-temperature curing of each fluororesin film”.

Table 1-5 shows the results.

TABLE 1-5 Curing method (i) (Reference example) (ii) (iii) (iv)Photosensitive Contact Film Contact Film Contact Film Contact Film resinangle (°) thickness (nm) angle (°) thickness (nm) angle (°) thickness(nm) angle (°) thickness (nm) composition 1 s 10 s Before After 1 s 10 sBefore After 1 s 10 s Before After 1 s 10 s Before After 1-1 55 55 53005300 54 46 5200 4200 55 45 5300 4150 56 56 5200 5200 1-2 58 58 5200 520055 45 5250 4300 57 46 5200 4250 57 57 5250 5250 1-3 59 59 5250 5250 5655 5100 5050 56 56 5250 5200 60 60 5100 5100 1-4 57 57 5100 5100 55 545150 5050 56 55 5100 5050 58 58 5150 5150 1-5 56 56 5150 5150 56 42 53003900 55 41 5150 4000 55 55 5300 5300 1-6 58 58 5100 5100 55 43 5200 410054 42 5100 4050 59 59 5200 5200 1-7 56 56 5200 5200 53 39 5100 3950 5440 5200 4100 57 57 5100 5100 1-8 60 60 5250 5250 55 41 5250 4050 53 405250 3950 58 58 5250 5200 1-9 54 54 5100 5100 53 52 5000 4950 53 53 51005000 47 32 5000 4700  1-10 56 56 5200 5200 54 53 5050 4900 55 54 52005150 49 36 5050 4550 Comparative 1-1 55 55 5150 5150 54 32 5100 3900 5429 5150 3800 35 21 5100 3500 Comparative 1-2 54 54 5150 5150 53 33 52003800 54 30 5150 3750 31 19 5200 3300 Comparative 1-3 55 55 5200 5200 5543 5100 4100 53 40 5200 4050 30 15 5100 3600 Comparative 1-4 55 55 50505050 54 42 5000 4050 55 41 5050 4100 27 20 5000 3500 Comparative 1-5 5656 5300 5300 56 39 5200 3500 54 38 5300 3600 33 18 5200 3250 Comparative1-6 53 53 5200 5200 54 39 5100 3600 54 37 5200 3650 28 14 5100 3600

Curing the photosensitive resins 1-1 to 1-8 by the method (iv) yieldedresults equivalent to those of the reference examples obtained by curingby the method (i), resulting in good cured films.

In contrast, curing the comparative photocurable fluororesins 1-1 to 1-3by the method (iv) yielded poor results as compared to curing by themethod (i). Curing the photosensitive resins 1-1 to 1-8 by the method(ii) or (iii) yielded good results among the photosensitive resins 1-3,1-4, 1-9, and 1-10.

7. Evaluation of Banks

The photosensitive resin compositions 1-1 to 1-10 and the comparativephotosensitive resin compositions 1-1 to 1-6 obtained in “5. Preparationof photosensitive resin compositions” were used to form banks 1-1 to1-10 and comparative banks 1-1 to 1-6, respectively, by the followingmethod, and the bank properties were evaluated and compared.

[Formation of Banks]

A 10-cm square ITO substrate was washed with ultrapure water and thenacetone. Subsequently, the substrate was subjected to UV-ozone treatmentfor five minutes using the UV-ozone treatment described above. Then, thephotosensitive resin compositions 1-1 to 1-10 and the comparativephotosensitive resin compositions 1-1 to 1-6 obtained in “5. Preparationof photosensitive resin compositions” were each applied to theUV-ozone-treated substrate using a spin coater at a rotation speed of1000 rpm, followed by heating on a hot plate at 90° C. for 150 seconds.Thus, fluororesin films and comparative fluororesin films each having athickness of 5 μm were formed. Each resulting resin film was exposed toi-rays (wavelength: 365 nm) using a mask aligner (available from SUSSMicroTec Group) with a mask having a 5-μm line-and-space pattern. Theresulting film was immersed in an alkali developer for 80 seconds, andthen washed with ultrapure water for 60 seconds. Subsequently, theresulting patterned film was heated at 90° C. for one hour (baking step)and subjected to UV-ozone treatment for five minutes, followed byheating at 90° C. for one hour.

The resulting resin film was subjected to evaluation of solubility inthe developer during the step, evaluation of bank properties(sensitivity and resolution), and contact angle measurement.

[Solubility in Developer]

The resin film on the ITO substrate after exposure was immersed in analkali developer at room temperature for 80 seconds to evaluate thesolubility in the alkali developer. The alkali developer was a 2.38 mass% tetramethylammonium hydroxide aqueous solution (hereinafter sometimesreferred to as TMAH). The solubility of the banks was evaluated bymeasuring the thickness of the banks after immersion using a contactfilm thickness meter. The banks were evaluated as “soluble” whencompletely dissolved, and “insoluble” when the resist film remainedundissolved.

Table 1-6 shows the results.

[Resist Properties (Sensitivity and Resolution)]

The optimal exposure Eop (mJ/cm²) for forming banks arranged in theline-and-space pattern was determined and used as an index forsensitivity.

The resulting pattern of banks was observed under a microscope toevaluate the resolution. A pattern without visible line-edge roughnesswas evaluated as “excellent”; a pattern with slightly visible line-edgeroughness was evaluated as “good”; and a pattern with significantline-edge roughness was evaluated as “poor”.

Table 1-6 shows the results.

[Contact Angle]

For the entire substrate surface having the banks obtained in the abovestep, the contact angle between the bank or comparative bank surface andanisole was measured. For the rest of the film, the exposed portionswith little temporal change in contact angle were considered as good,and the non-exposed portions with a low contact angle were considered asgood.

Table 1-6 shows the results.

TABLE 1-6 Banks 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 1-9 Photosensftive resincomposition 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 1-9 Solubility Non-exposedSoluble Soluble Soluble Soluble Soluble Soluble Soluble Soluble Solubleindeveloper portions Exposed portions Insoluble Insoluble InsolubleInsoluble Insoluble Insoluble Insoluble Insoluble Insoluble Resistproperties Sensitivity 200  205  202  206  205  200  199  210  200 (mJ/cm²) Resolution Excellent Excellent Excellent Excellent ExcellentExcellent Excellent Excellent Excellent Contact angle (°)  1 s 10 10 1010 10 10 10 10 10 Non-exposed portions 10 s 10 10 10 10 10 10 10 10 10Contact angle (°)  1 s 50 57 60 56 55 50 57 58 47 Exposed portions 10 s50 57 60 56 55 50 57 58 32 Comparative Comparative ComparativeComparative Comparative Comparative Banks 1-10 1-1 1-2 1-3 1-4 1-5 1-6Photosensftive resin composition 1-10 Comparative ComparativeComparative Comparative Comparative Comparative 1-1 1-2 1-3 1-4 1-5 1-6Solubility Non-exposed Soluble Soluble Soluble Soluble Soluble SolubleSoluble indeveloper portions Exposed portions Insoluble InsolubleInsoluble Insoluble Insoluble Insoluble Insoluble Resist propertiesSensitivity 210  205  210  200  204  205  205  (mJ/cm²) ResolutionExcellent Excellent Excellent Excellent Excellent Excellent ExcellentContact angle (°)  1 s 10 10 10 10 10 10 10 Non-exposed portions 10 s 1010 10 10 10 10 10 Contact angle (°)  1 s 49 35 31 30 27 33 28 Exposedportions 10 s 36 21 19 15 20 18 14

The evaluation of solubility in the developer shows that the banks orcomparative banks were made of a negative resist in which only thenon-exposed portions are soluble. The evaluation of the bank propertiesshows that the banks and comparative banks had comparable sensitivityand “excellent” resolution in which the 5-μm line-and-space pattern ofthe mask was transferred with good resolution without visible line-edgeroughness. Specifically, these evaluations show that the fluororesins ofthe present disclosure and the comparative fluororesins only slightlyinfluenced the banks.

In contrast, regarding the banks, the films heated at 90° C. after theUV-ozone treatment showed no temporal change in contact angle withrespect to anisole, with sufficient curing even at low temperatures,resulting in good banks with high liquid repellency.

Second Embodiment

A fluororesin according to the second embodiment of the presentdisclosure contains a repeating unit represented by a formula (2-1) anda repeating unit represented by the formula (2-2).

In the formula (2-1), R²⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group; R²⁻² represents a hydrogen atom or a C1-C6 linear,C3-C6 branched, or C3-C6 cyclic alkyl group; R²⁻³ and R²⁻⁴ eachindependently represent a fluorine atom, a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, or a C1-C10 linear, C3-C10branched, or C3-C10 cyclic fluoroalkyl group; and one or more of R²⁻¹,R²⁻³, and R²⁻⁴ are fluorine atoms or the fluoroalkyl groups.

In the formula (2-2), R²⁻⁵ and R²⁻⁶ each independently represent ahydrogen atom or a methyl group; W² is a divalent linking group andrepresents —O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—,or —C(═O)—NH—; A² is a divalent linking group and represents a C1-C10linear, C3-C10 branched, or C3-C10 cyclic alkylene group in which one ormore hydrogen atoms in the alkylene group may be substituted by hydroxygroups or —O—C(═O)—CH₃; Y² is a divalent linking group and represents—O— or —NH—; and n represents an integer of 1 to 3.

The molecular weight of the fluororesin in terms of weight averagemolecular weight measured by gel permeation chromatography (GPC) usingpolystyrene as a standard substance is preferably 1000 or more and1000000 or less, more preferably 2000 or more and 500000 or less,particularly preferably 3000 or more and 100000 or less. When themolecular weight is less than 1000, the resulting fluororesin film orbanks for organic EL tend to have a low strength. When the molecularweight is more than 1000000, it may be difficult to form a fluororesinfilm due to lack of solubility of the fluororesin in solvents.

The dispersity (Mw/Mn) is preferably 1.01 to 5.00, more preferably 1.01to 4.00, particularly preferably 1.01 to 3.00.

The fluororesin may be a random copolymer, an alternating copolymer, ablock copolymer, or a graft copolymer. Preferably, the fluororesin is arandom copolymer to suitably (not locally) disperse characteristics ofeach repeating unit.

The fluororesin may be a polymer containing a combination of one or moretypes of units each corresponding to a repeating unit represented by theformula (2-1) and one or more types of units each corresponding to arepeating unit represented by the formula (2-2).

The fluororesin may be a mixture (blend) of such polymers.

Preferably, the fluororesin has a fluorine content of 20 mass % or moreand 80 mass % or less relative to 100 mass % of the fluororesin. Thefluororesin having a fluorine content in the above ranges is easilysoluble in solvents. A fluororesin film or banks having excellent liquidrepellency can be obtained because the fluororesin contains fluorineatoms.

The following describes the repeating unit represented by the formula(2-1).

In the formula (2-1), R²⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group. A hydrogen atom and a methyl group are preferred.

In the formula (2-1), R²⁻² represents a hydrogen atom or a C1-C6 linear,C3-C6 branched, or C3-C6 cyclic alkyl group.

Examples of R²⁻² include a hydrogen atom, a methyl group, an ethylgroup, an n-propyl group, an isopropyl group, an n-butyl group, a1-methylpropyl group, a 2-methylpropyl group, a tert-butyl group, ann-pentyl group, an isopentyl group, a 1,1-dimethylpropyl group, a1-methylbutyl group, a 1,1-dimethylbutyl group, an n-hexyl group, acyclopentyl group, and a cyclohexyl group. A hydrogen atom, a methylgroup, an ethyl group, an n-propyl group, and an isopropyl group arepreferred. A hydrogen atom and a methyl group are more preferred.

In the formula (2-1), R²⁻³ and R²⁻⁴ each independently represent afluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylgroup, or a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic fluoroalkylgroup; and one or more of R²⁻¹, R²⁻³, and R²⁻⁴ are fluorine atoms or thefluoroalkyl groups.

When R²⁻³ and R²⁻⁴ each independently represent a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, examples thereof include amethyl group, an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, a 1-methylpropyl group, a 2-methylpropyl group, atert-butyl group, an n-pentyl group, an isopentyl group, a1,1-dimethylpropyl group, a 1-methylbutyl group, a 1,1-dimethylbutylgroup, an n-hexyl group, a cyclopentyl group, and a cyclohexyl group. Amethyl group, an ethyl group, an n-propyl group, and an isopropyl groupare preferred.

R²⁻³ and R²⁻⁴ each independently preferably represent a fluorine atom, atrifluoromethyl group, a difluoromethyl group, a pentafluoroethyl group,a 2,2,2-trifluoroethyl group, an n-heptafluoropropyl group, a2,2,3,3,3-pentafluoropropyl group, a 3,3,3-trifluoropropyl group, ahexafluoroisopropyl group, a heptafluoroisopropyl group, ann-nonafluorobutyl group, an isononafluorobutyl group, or atert-nonafluorobutyl group; more preferably a fluorine atom, atrifluoromethyl group, a difluoromethyl group, a pentafluoroethyl group,a 2,2,2-trifluoroethyl group, an n-heptafluoropropyl group, a2,2,3,3,3-pentafluoropropyl group, a 3,3,3-trifluoropropyl group, or ahexafluoroisopropyl group; particularly preferably a fluorine atom, adifluoromethyl group, or a trifluoromethyl group.

The following are examples of preferred structures of the repeating unitrepresented by the formula (2-1).

The amount of the repeating unit represented by the formula (2-1) in thefluororesin is preferably 5 mass % or more and 70 mass % or less, morepreferably 10 mass % or more and 50 mass % or less, particularlypreferably 10 mass % or more and 30 mass % or less, relative to 100 mass% of the fluororesin.

When the amount of the repeating unit represented by the formula (2-1)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents. When the amount of the repeating unit represented by theformula (2-1) is less than 5 mass %, the resistance against UV-ozonetreatment or oxygen plasma treatment tends to decrease.

Depending on use, for example, a method in which the fluororesin isdirectly pressed under heat without being dissolved in solvents (i.e., ahot-press method) can be used to form a fluororesin film. In this case,use of the repeating unit represented by the formula (2-1) in an amountof more than 70 mass % does not result in either poor resistance of thewhole fluororesin to UV-ozone treatment or oxygen plasma treatment orpoor ink repellency after UV-ozone treatment or oxygen plasma treatment,and such use is thus not avoided in the present disclosure.

Here, it is assumed, although not confirmed, that the repeating unitrepresented by the formula (2-1) according to the second embodiment ofthe present disclosure has the following effects. The effects of thefluororesin according to the second embodiment of the present disclosuredescribed herein are not intended to be exhaustive.

The repeating unit represented by the formula (2-1) has an effect ofimparting ink repellency after UV-ozone treatment or oxygen plasmatreatment. Preferably, R²⁻³ and R²⁻⁴ are each a fluorine atom or aC1-C10 linear, C3-C10 branched, or C3-C10 cyclic fluoroalkyl group,because the above effect is particularly high in such a case.

Further, the repeating unit represented by the formula (2-1) has aneffect of increasing the resistance to UV-ozone treatment or oxygenplasma treatment. The possible reasons are as follows.

Generally, the ester bond is considered to be reactive with and not veryresistant to UV-ozone treatment or oxygen plasma treatment (also seecomparative fluororesin films 2-1 to 2-10 and Table 2-9 describedlater). Thus, in a fluoropolymer consisting of acrylic sites having anester bond adjacent to the main chain, the ester bond becomes a reactivesite. Presumably, this results in low resistance of the fluoropolymer tothe UV-ozone treatment or oxygen plasma treatment (e.g., fluoropolymersdisclosed in Patent Literatures 3 and 4).

In contrast, the repeating unit represented by the formula (2-1)according to the second embodiment of the present disclosure has astructure consisting of hydrocarbons without substituents mainlycontaining oxygen such as an ester bond that is reactive with UV-ozonetreatment or oxygen plasma treatment. Thus, the presence of therepeating unit represented by the formula (2-1) in the resin is presumedto increase the resistance of the fluororesin according to the secondembodiment of the present disclosure to the UV-ozone treatment or oxygentreatment.

The following describes the repeating unit represented by the formula(2-2).

In the formula (2-2), R²⁻⁵ and R²⁻⁶ each independently represent ahydrogen atom or a methyl group.

In the formula (2-2), W² is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—.Preferred of these are —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, and —C(═O)—NH—.

The fluororesin according to the second embodiment of the presentdisclosure in which W² is —O—C(═O)—NH— has better ink repellency afterUV-ozone treatment or oxygen plasma treatment, and is thus oneparticularly preferred embodiment.

In the formula (2-2), A² is a divalent linking group and represents aC1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylene group in whichone or more hydrogen atoms in the alkylene group may be substituted byhydroxy groups or —O—C(═O)—CH₃.

When the divalent linking group A² is a C1-C10 linear alkylene group,examples thereof include a methylene group, an ethylene group, apropylene group, an n-butylene group, an n-pentylene group, ann-hexalene group, an n-heptalene group, an n-octalene group, ann-nonalene group, and an n-decalene group.

When the divalent linking group A² is a C3-C10 branched alkylene group,examples thereof include an isopropylene group, an isobutylene group, asec-butylene group, a tert-butylene group, an isopentalene group, and anisohexalene group.

When the divalent linking group A² is a C3-C10 cyclic alkylene group,examples thereof include a cyclopropyl group, a cyclobutyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, a cyclodecanyl group, and a 4-tert-butylcyclohexyl group.

When one or more hydrogen atoms in these alkylene groups are substitutedby hydroxy groups, examples of these hydroxy group-substituted alkylenegroups include a hydroxyethylene group, a 1-hydroxy-n-propylene group, a2-hydroxy-n-propylene group, a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—), a 1-hydroxy-n-butylene group, a 2-hydroxy-n-butylenegroup, a hydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—), ahydroxy-isobutylene group (—CH₂CH(CH₂OH)CH₂—), and ahydroxy-tert-butylene group (—C(CH₂OH)(CH₃)CH₂—).

When one or more hydrogen atoms in these alkylene groups are substitutedby —O—C(═O)—CH₃, examples of these substituted-alkylene groups includethose in which hydroxy groups of the hydroxy group-substituted alkylenegroups exemplified above are substituted by —O—C(═O)—CH₃.

Preferably, the divalent linking group A² is a methylene group, anethylene group, a propylene group, an n-butylene group, an isobutylenegroup, a sec-butylene group, a cyclohexyl group, a 2-hydroxy-n-propylenegroup, a hydroxy-isopropylene group (—CH(CH₂OH)CH₂—), a2-hydroxy-n-butylene group, or a hydroxy-sec-butylene group(—CH(CH₂OH)CH₂CH₂—); more preferably an ethylene group, a propylenegroup, a 2-hydroxy-n-propylene group, or a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—); particularly preferably an ethylene group or a2-hydroxy-n-propylene group.

In the formula (2-2), Y² is a divalent linking group and represents —O—or —NH—, with —O— being more preferred.

In the formula (2-2), n represents an integer of 1 to 3, with n of 1being particularly preferred.

The substituents are each independently in the ortho, meta, or paraposition of the aromatic ring, with the para position being preferred.

The following are examples of preferred structures of the repeating unitrepresented by the formula (2-2). In the examples, the substituentposition in the aromatic ring is the para position. Yet, thesubstituents may be each independently in the ortho or meta position.

The amount of the repeating unit represented by the formula (2-2) in thefluororesin is preferably 5 mass % or more and 70 mass % or less, morepreferably 10 mass % or more and 50 mass % or less, particularlypreferably 10 mass % or more and 30 mass % or less, relative to 100 mass% of the fluororesin.

When the amount of the repeating unit represented by the formula (2-2)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents. When the amount of the repeating unit represented by theformula (2-1) is less than 5 mass %, the resistance against UV-ozonetreatment or oxygen plasma treatment tends to decrease.

Here, it is assumed, although not confirmed, that the repeating unitrepresented by the formula (2-2) according to the second embodiment ofthe present disclosure has an effect of exhibiting resistance toUV-ozone treatment oxygen plasma. The effects of the fluororesinaccording to the second embodiment of the present disclosure describedherein are not intended to be exhaustive.

The fluororesin according to the second embodiment of the presentdisclosure may be, as described above, a mixture (blend) of a copolymercontaining a repeating unit represented by the formula (2-1) and arepeating unit represented by the formula (2-2) and another copolymercontaining a repeating unit represented by the formula (2-1) and arepeating unit represented by the formula (2-2). Specifically, in onepreferred second embodiment of the present disclosure, the fluororesinaccording to the second embodiment of the present disclosure is amixture of a fluororesin containing a repeating unit represented by theformula (2-2) wherein W² is —O—C(═O)—NH— and a fluororesin containing arepeating unit represented by the formula (2-2) wherein W² is—C(═O)—NH—.

Preferably, the fluororesin according to the second embodiment of thepresent disclosure further contains a repeating unit represented by thefollowing formula (2-3).

In the formula (2-3), R²⁻⁷ represents a hydrogen atom or a methyl group;

In the formula (2-3), R²⁻⁸ represents a C1-C15 linear, C3-C15 branched,or C3-C15 cyclic alkyl group in which one or more hydrogen atoms in thealkyl group are substituted by fluorine atoms; and the repeating unithas a fluorine content of 30 mass % or more.

When R²⁻⁸ is a linear hydrocarbon group, specific examples include amethyl group, an ethyl group, a propyl group, a butyl group, a pentylgroup, a hexyl group, a heptyl group, an octyl group, a nonyl group, andC10-C14 linear alkyl groups in which one or more hydrogen atoms aresubstituted by fluorine atoms.

The fluororesin according to the second embodiment of the presentdisclosure may be a polymer containing a combination of a repeating unitrepresented by the formula (2-3), a repeating unit represented by theformula (2-1), and a repeating unit represented by the formula (2-2).

The fluororesin may also be a mixture (blend) of a polymer containing arepeating unit represented by the formula (2-3) and a polymer containinga repeating unit represented by the formula (2-1) and a repeating unitrepresented by the formula (2-2). When the fluororesin is a mixture, thefluororesin may be a mixture of a polymer containing a repeating unitrepresented by the formula (2-3) and a polymer containing a repeatingunit represented by the formula (2-1) and a repeating unit representedby the formula (2-2), or a mixture of a polymer containing a repeatingunit represented by the formula (2-3) and a repeating unit representedby the formula (2-2) and a polymer containing a repeating unitrepresented by the formula (2-1).

When R²⁻⁸ is a linear hydrocarbon group, preferably, the repeating unitrepresented by the formula (2-3) is a repeating unit represented by thefollowing formula (2-3-1).

wherein R²⁻⁷ is the same as R²⁻⁷ in the formula (2-3); X is a hydrogenatom or a fluorine atom; p is an integer of 1 to 4; and q is an integerof 1 to 14.

In the repeating unit represented by the formula (2-3-1), particularlypreferably, p is an integer of 1 or 2, q is an integer of 2 to 8, and Xis a fluorine atom.

The following are examples of preferred structures of the repeating unitrepresented by the formula (2-3).

The amount of the repeating unit represented by the formula (2-3) ispreferably 5 mass % or more and 70 mass % or less, more preferably 10mass % or more and 50 mass % or less, particularly preferably 10 mass %or more and 30 mass % or less, relative to 100 mass % of thefluororesin.

When the amount of the repeating unit represented by the formula (2-3)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents.

The repeating unit represented by the formula (2-3) is a repeating unitthat imparts ink repellency after UV-ozone treatment or oxygen plasmatreatment. Thus, when pursuing high ink repellency, preferably, thefluororesin according to the second embodiment of the present disclosurecontains the repeating unit represented by the formula (2-3).

Preferably, the fluororesin according to the second embodiment of thepresent disclosure further contains a repeating unit represented by aformula (2-4).

The fluororesin according to the second embodiment of the presentdisclosure may be a polymer containing a combination of a repeating unitrepresented by the formula (2-4), a repeating unit represented by theformula (2-1), and a repeating unit represented by the formula (2-2).Alternatively, the fluororesin may be a polymer containing a combinationof a repeating unit represented by the formula (2-4), a repeating unitrepresented by the formula (2-1), a repeating unit represented by theformula (2-2), and a repeating unit represented by the formula (2-3).

The fluororesin may also be a mixture (blend) of a polymer containing arepeating unit represented by the formula (2-4) and a polymer containinga repeating unit represented by the formula (2-1) and a repeating unitrepresented by the formula (2-2). When the fluororesin is a mixture, thefluororesin may be a mixture of a polymer containing a repeating unitrepresented by the formula (2-4) and a repeating unit represented by theformula (2-1) and a polymer containing a repeating unit represented bythe formula (2-2), or a mixture of a polymer containing a repeating unitrepresented by the formula (2-4) and a repeating unit represented by theformula (2-2) and a polymer containing a repeating unit represented bythe formula (2-1). Further, when the fluororesin is a mixture containinga repeating unit represented by the formula (2-3), the fluororesin maybe a mixture of a repeating unit represented by the formula (2-3) andany of the above possible combinations of the repeating unitsrepresented by the formulas (2-1), (2-2), and (2-4).

In the formula (2-4), R²⁻⁹ represents a hydrogen atom or a methyl group.

In the formula (2-4), each B² independently represents a hydroxy group,a carboxy group, —C(═O)—O—R²⁻¹⁰ (R²⁻¹⁰ represents a C1-C15 linear,C3-C15 branched, or C3-C15 cyclic alkyl group in which one or morehydrogen atoms in the alkyl group are substituted by fluorine atoms, andR²⁻¹⁰ has a fluorine content of 30 mass % or more), or —O—C(═O)—R²⁻¹¹(R²⁻¹¹ represents a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup).

When B² is —C(═O)—O—R²⁻¹⁰, specific examples of R²⁻¹⁰ may include thoseof R²⁻⁸ in the formula (2-3).

When B² is —O—C(═O)—R²⁻¹¹, examples of R²⁻¹¹ include a methyl group, anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a1-methylpropyl group, a 2-methylpropyl group, a tert-butyl group, ann-pentyl group, an isopentyl group, a 1,1-dimethylpropyl group, a1-methylbutyl group, a 1,1-dimethylbutyl group, an n-hexyl group, acyclopentyl group, and a cyclohexyl group. A hydrogen atom, a methylgroup, an ethyl group, an n-propyl group, and an isopropyl group arepreferred. A methyl group is more preferred.

In the formula (2-4), m represents an integer of 0 to 3.

The following are examples of preferred structures of the repeating unitrepresented by the formula (2-4).

The amount of the repeating unit represented by the formula (2-4) ispreferably 5 mass % or more and 70 mass % or less, more preferably 10mass % or more and 50 mass % or less, particularly preferably 20 mass %or more and 40 mass % or less, relative to 100 mass % of thefluororesin.

When the amount of the repeating unit represented by the formula (2-4)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents.

A repeating unit represented by the formula (2-4) wherein B² is ahydroxy group or a carboxy group has solubility in an alkali developer.Thus, when it is desired to impart alkali developability to a filmobtainable from the fluororesin, preferably, the fluororesin accordingto the second embodiment of the present disclosure contains therepeating unit represented by the formula (2-4) wherein B² is a hydroxygroup or a carboxy group. Specifically, when it is desired to form bankscontaining a repeating unit represented by the formula (2-1) and arepeating unit represented by the formula (2-2A) in the secondembodiment of the present disclosure, further adding the repeating unitrepresented by the formula (2-4) wherein B² is a hydroxy group or acarboxy group tends to improve the shape of the resulting patternedfilm, thus providing one preferred embodiment.

A monomer corresponding to the repeating unit represented by the formula(2-4) wherein B² is a hydroxy group or a carboxy group can also be usedas a monomer (formula (2-2a)) of a repeating unit represented by theformula (2-2) (described later).

Particularly preferred embodiments of the fluororesin according to thesecond embodiment of the present disclosure may include the followingfour embodiments.

Embodiment 2-1

Fluororesin containing a repeating unit represented by the followingformula (2-1) and a repeating unit represented by the following formula(2-2)Formula (2-1): R²⁻¹ and R²⁻² are hydrogen atoms; and R²⁻³ and R²⁻⁴ areeach independently a fluorine atom, a difluoromethyl group, or atrifluoromethyl group.Formula (2-2): R²⁻⁵ and R²⁻⁶ are hydrogen atoms; W² is —O—C(═O)—NH—,—C(═O)—O—C(═O)—NH—, or —C(═O)—NH—; A² is an ethylene group; Y² is —O—;and n is 1.

Embodiment 2-2

Fluororesin containing a repeating unit represented by the followingformula (2-1) and a repeating unit represented by the following formula(2-2)Formula (2-1): same as described in Embodiment 2-1Formula (2-2): R²⁻⁵ and R²⁻⁶ are hydrogen atoms; W² is —O—;A² is a 2-hydroxy-n-propylene group or a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—); Y² is —O—; and n is 1.

Embodiment 2-3

Fluororesin containing repeating units represented by the followingformulas (2-1), (2-2), and (2-3-1)Formula (2-1): same as described in Embodiment 2-1Formula (2-2): same as described in Embodiment 2-1Formula (2-3-1): R²⁻⁷ is a methyl group; p is an integer of 2; q is aninteger of 4 to 8; and X is a fluorine atom.

Embodiment 2-4

Fluororesin containing repeating units represented by the followingformulas (2-1), (2-2), (2-3-1), and (2-4)Formula (2-1): same as described in Embodiment 2-1Formula (2-2): same as described in Embodiment 2-1Formula (2-3-1): same as described in Embodiment 2-1formula (2-4): R²⁻⁹ is a hydrogen atom; B² is a hydroxy group or acarboxy group; and m is 1.

The fluororesin according to the second embodiment of the presentdisclosure can be easily produced by the following two steps: first,monomers represented by formulas (2-1a) and (2-2a) are polymerized toobtain a fluororesin precursor containing a repeating unit representedby the formula (2-1) and a repeating unit represented a formula (2-2b);and then the repeating unit represented by the formula (2-2b) betweenthe repeating unit represented by the formula (2-1) and the repeatingunit represented by the formula (2-2b) is subjected to addition reactionor condensation reaction with an acrylic acid derivative represented bya formula (2-2c).

In the formula (2-1), R²⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group; R²⁻² represents a hydrogen atom or a C1-C6 linear.C3-C6 branched, or C3-C6 cyclic alkyl group; R²⁻³ and R²⁻⁴ eachindependently represent a fluorine atom, a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, or a C1-C10 linear, C3-C10branched, or C3-C10 cyclic fluoroalkyl group; and one or more of R²⁻¹,R²⁻³, and R²⁻⁴ are fluorine atoms or the fluoroalkyl groups.

In the formula (2-1a), R²⁻¹, R²⁻², R²⁻³, and R²⁻⁴ are the same as R²⁻¹,R²⁻², R²⁻³, and R²⁻⁴ in the formula (2-1), respectively.

In the formula (2-2), R²⁻⁵ and R²⁻⁶ each independently represent ahydrogen atom or a methyl group; W² is a divalent linking group andrepresents —O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—,or —C(═O)—NH—; A² is a divalent linking group and represents a C1-C10linear, C3-C10 branched, or C3-C10 cyclic alkylene group in which one ormore hydrogen atoms in the alkylene group may be substituted by hydroxygroups or —O—C(═O)—CH₃; Y² is a divalent linking group and represents—O— or —NH—; and n represents an integer of 1 to 3.

In the formula (2-2a), R²⁻⁵ and n are the same as R²⁻⁵ and n in theformula (2-2), respectively; and D² represents a hydroxy group or acarboxy group.

In the formula (2-2b), R²⁻⁵, n, and D² are the same as R²⁻⁵ and n in theformula (2-2) and D² in the formula (2-2a), respectively.

In the formula (2-2c), R²⁻⁶, A², and Y² are the same as R²⁻⁶, A², and Y²in the formula (2-2), respectively; and Z² represents an isocyanategroup (—N═C═O), an acid halide (—C(═O)—X, X is a halogen atom or animidazolyl group), an acid anhydride, a halogen atom, a hydroxy group,an amino group (—NH₂), or an oxirane group.

In the formulas (2-2), (2-2a), (2-2b), and (2-2c), the substituents areeach independently in the ortho, meta, or para position of the aromaticring.

Each step is described below.

[First Step]

In the first step, monomers represented by the formulas (2-1a) and(2-2a) are polymerized to produce a fluororesin precursor containing arepeating unit represented by the formula (2-1) and a repeating unitrepresented by the formula (2-2b).

The monomer represented by the formula (2-1a) may be a commerciallyavailable product or can be prepared by a known method or a method basedthereon. For example, preferably, the monomer is prepared by a methoddescribed in Journal of Organic Chemistry, 1970, Vol. 35, No. 6, pp.2096-2099, or a method based thereon.

The repeating unit represented by the formula (2-1) is formed bycleavage of the polymerizable double bond of the monomer represented bythe formula (2-1a). No structural changes occur and the originalstructure is maintained, except for the changes in the polymerizabledouble bond during polymerization. Thus, in the monomer represented bythe formula (2-1a), R²⁻¹, R²⁻², R²⁻³ and R²⁻⁴ are the same as R²⁻¹,R²⁻², R²⁻³, and R²⁻⁴ in the repeating unit represented by the formula(2-1), respectively. Examples of specific substituents may include thosedescribed in the description of the repeating unit represented by theformula (2-1). Examples of preferred structures of the monomerrepresented by the formula (2-1a) may include those of the respectivemonomers before cleavage of the polymerizable double bond in therepeating units exemplified in the description of the repeating unitrepresented by the formula (2-1).

The monomer represented by the formula (2-2a) may be a commerciallyavailable product or can be prepared by a known method or a method basedthereon. Use of a commercially available product is preferred in termsof easy availability.

The repeating unit represented by the formula (2-2b) is formed bycleavage of the polymerizable double bond of the monomer represented bythe formula (2-2a). No structural changes occur and the originalstructure is maintained, except for the changes in in the polymerizabledouble bond during polymerization.

In the monomer represented by the formula (2-2a), preferably, R²⁻⁵ is ahydrogen atom and n is 1. Specifically, a particularly preferredstructure is one in which R²⁻⁵ is a hydrogen atom, D² is a hydroxygroup, and n is 1; or one in which R²⁻⁵ is a hydrogen atom, D² is acarboxy group, and n is 1.

The method of polymerizing the monomers represented by the formulas(2-1a) and (2-2a) is now described.

Any common polymerization method can be used, but radical polymerizationand ionic polymerization are preferred. In some cases, polymerizationmethods such as coordination anionic polymerization, living anionicpolymerization, cationic polymerization, ring-opening metathesispolymerization, vinylene polymerization, and vinyl addition can also beused. Of these, radical polymerization is particularly preferred. Thesepolymerization methods may be known methods. The radical polymerizationmethod is described below, but polymerization can be easily performedalso by other methods according to known documents or the like.

The radical polymerization may be performed in a batch type,semi-continuous type, or continuous-type operation by a knownpolymerization method such as bulk polymerization, solutionpolymerization, suspension polymerization, or emulsion polymerization inthe presence of a radical polymerization initiator or radical initiationsource.

Any radical polymerization initiator may be used. Examples thereofinclude azo compounds, peroxide compounds, persulfate compounds, andredox compounds. Particularly preferred are2,2′-azobis(2-methylbutyronitrile), dimethyl2,2′-azobis(2-methylpropionate), tert-butyl peroxypivalate,di-tert-butyl peroxide, isobutyryl peroxide, lauroyl peroxide, succinicacid peroxide, dicinnamyl peroxide, di-n-propyl peroxydicarbonate,tert-butylperoxyallyl monocarbonate, benzoyl peroxide, hydrogenperoxide, and ammonium persulfate.

Any reaction vessel may be used for polymerization. Preferably,polymerization is performed using a polymerization solvent in additionto the monomers and initiators. A polymerization solvent that does notinterfere with radical polymerization is preferred. Typical examplesthereof include ester solvents such as ethyl acetate and n-butylacetate; ketone solvents such as acetone, methyl ethyl ketone, andmethyl isobutyl ketone; hydrocarbon solvents such as toluene andcyclohexane; and alcohol solvents such as methanol, isopropyl alcohol,and ethylene glycol monomethyl ether. Solvents such as water, chainether solvents, cyclic ether solvents, chlorofluorocarbon solvents, andaromatic solvents can also be used. These polymerization solvents can beused alone or in combination of two or more thereof. A molecular weightmodifier such as mercaptan may also be used in combination. The reactiontemperature for polymerization is suitably changed according to aradical polymerization initiator or radical polymerization initiatingsource. Usually, the reaction temperature is preferably 20° C. to 200°C., more preferably 30° C. to 140° C., particularly preferably 50° C. to120° C.

The polymerization time is usually 0.1 to 48 hours, preferably 1 to 24hours. Preferably, a point at which the monomer is consumed isdetermined, by an analytical instrument such as a high-performanceliquid chromatograph (HPLC) or nuclear magnetic resonance (NMR) device,as the endpoint of the polymerization. After completion of thepolymerization, the reaction can be terminated by cooling thepolymerization solution to room temperature or below.

The monomer concentration relative to 100 mass % of the polymerizationsystem at the beginning of polymerization is preferably 1 mass % or moreand 95 mass % or less, more preferably 10 mass % or more and 80 mass %or less. When the monomer concentration is lower than the above ranges,the reaction rate during polymerization tends to decrease. When themonomer concentration is higher than the above ranges, thepolymerization solution tends to be highly viscous.

The organic solvent or water can be removed from the resultingfluororesin precursor solution or dispersion by a method such asreprecipitation, filtration, or vacuum thermal distillation. Further,the resulting fluororesin precursor may be purified by, for example, amethod such as washing with a solvent that does not dissolve thefluororesin during filtration.

[Second Step]

In the second step, the formula (2-2b) between the repeating unitrepresented by the formula (2-1) and the repeating unit represented bythe formula (2-2b) is subjected to addition reaction or condensationreaction with an acrylic acid derivative represented by the formula(2-2c) to produce a fluororesin containing repeating units representedby the formulas (2-1) and (2-2).

The acrylic acid derivative represented by the formula (2-2c) may be acommercially available product or can be prepared by a known method or amethod based thereon. Use of a commercially available product ispreferred in terms of easy availability.

In the formula (2-2c), R²⁻⁶, A², and Y² are the same as R²⁻⁶, A², and Y²in the formula (2-2), respectively. Examples of specific substituentsmay include those of R²⁻⁶, A², and Y² described in the description ofthe repeating unit represented by the formula (2-2)

Z² represents an isocyanate group (—N═C═), an acid halide (—C(═O)—X,wherein X is a halogen atom or an imidazolyl group), an acid anhydride,a halogen atom, a hydroxy group, a hydroxy group protected by aprotective group, an amino group (—NH₂), or an oxirane group.

Examples of the acid halide (—C(═O)—X, wherein X is a halogen atom or animidazolyl group) in Z² include acid fluorides such as —C(═O)—F,—C(═O)—Cl, —C(═O)—Br, and —C(═O)—I, and groups in which —C(═O)— islinked to a 2-imidazolyl group.

Examples of the acid anhydride in Z² include —C(═O)—O—C(═O)—CH₃,—C(═O)—O—C(═O)-(tert-butyl), and —C(═O)—O—C(═O)—CF₃.

Examples of the hydroxy group protected by a protective group in Z²include a hydroxy group protected by a protective group such as amethanesulfonyl group, a trifluoromethanesulfonyl group, or ap-toluenesulfonyl group.

Examples of the oxirane group in Z² include an ethylene oxide group, a1,2-propylene oxide group, and a 1,3-propylene oxide group. Of these, Z²is particularly preferably an isocyanate group, —C(═O)—Cl, or anethylene oxide group.

Examples of preferred acrylic acid derivatives represented by theformula (2-2c) include the following structures.

The reaction varies depending on the type of D² in the formula (2-2b)and the type of Z² in the formula (2-2c), but in any reaction, a commonaddition reaction method or condensation reaction method can be used.Here, three forms are exemplified.

Reaction (2-1): When D² in the formula (2-2b) is a hydroxy group and Z²in the formula (2-2c) is an isocyanate group, W² in the resultingformula (2-2) can form a bond “—O—C(═O)—NH—”.

Reaction (2-2): When D² in the formula (2-2b) is a carboxy group and Z²in the formula (2-2c) is an isocyanate group, W² in the resultingformula (2-2) can form a bond “—C(═O)—NH—” by decarboxylation in thesystem or can form a bond “—C(═O)—O—C(═O)—NH—” that does not involvedecarboxylation in the system.

Reaction (2-3): When C in the formula (2-2b) is a hydroxy group and Z²in the formula (2-2c) is an ethylene oxide group, W² in the resultingformula (2-2) can form a bond “—O—”.

The method of the second step is described below. In any of the abovereactions, usually, the following method can be used.

The amount of the acrylic acid derivative represented by the formula(2-2c) to act on the fluororesin precursor containing the repeatingunits represented by the formulas (2-1) and (2-2b) is not limited, butis usually 0.01 to 5 mol, preferably 0.05 to 3 mol, more preferably 0.05to 1 mol, per mole of the fluororesin precursor containing the repeatingunits represented by the formulas (2-1) and (2-2b). The amount of theacrylic acid derivative is particularly preferably 0.2 to 1 mol.

Usually, the reaction is performed using an aprotic solvent such asdichloroethane, toluene, ethylbenzene, monochlorobenzene,tetrahydrofuran, acetonitrile, propylene glycol monomethyl monoacetate(PGMEA), or N,N-dimethylformamide. These solvents may be used alone orin combination of two or more thereof.

The reaction temperature is not limited, and is usually in the range of−20° C. to +100° C., preferably 0° C. to +80° C., more preferably +10°C. to +40° C. Preferably, the reaction is performed with stirring.

The reaction time depends on the reaction temperature, but is usuallyseveral minutes to 100 hours, preferably 30 minutes to 50 hours, morepreferably 1 to 20 hours. Preferably, a point at which the acrylic acidderivative represented by the formula (2-2c) is consumed is determined,by an analytical instrument such as a nuclear magnetic resonance (NMR)device, as the endpoint of the reaction.

In this reaction, a base may be used as a catalyst. Examples ofpreferred bases include organic bases such as trimethylamine,triethylamine, tripropylamine, tributylamine, and diisopropylethylamine;and inorganic bases such as sodium hydroxide, potassium hydroxide, andlithium hydroxide. The amount of the base catalyst used is not limited,but is 0.01 to 5 mol, preferably 0.02 to 3 mol, more preferably 0.05 to1 mol, per mole of the fluororesin precursor containing the repeatingunits represented by the formulas (2-1) and (2-2b).

After completion of the reaction, usual techniques such asreprecipitation, filtration, extraction, crystallization, andrecrystallization are performed, whereby a fluororesin containing arepeating unit represented by the formula (2-1) and a repeating unitrepresented by the formula (2-2) can be obtained. Further, the resultingfluororesin may be purified by, for example, a method such as washingwith a solvent that does not dissolve the fluororesin during filtration.

The photosensitive resin composition according to the second embodimentof the present disclosure at least contains the fluororesin, a solvent,and a photopolymerization initiator.

The photosensitive resin composition according to the second embodimentof the present disclosure is particularly suitable as a negative resincomposition for obtaining a fluororesin film or banks for organic EL(described later).

In the photosensitive resin composition according to the secondembodiment of the present disclosure, any solvent that can dissolve thefluororesin may be used, and examples thereof include ketones, alcohols,polyhydric alcohols and their derivatives, ethers, esters, aromaticsolvents, and fluorine solvents. These may be used alone or incombination of two or more thereof.

Specific examples of the ketones include acetone, methyl ethyl ketone,cyclopentanone, cyclohexanone, methyl isoamyl ketone, 2-heptanonecyclopentanone, methyl isobutyl ketone, methyl isopentyl ketone, and2-heptanone.

Specific examples of the alcohols include isopropanol, butanol,isobutanol, n-pentanol, isopentanol, tert-pentanol, 4-methyl-2-pentanol,3-methyl-3-pentanol, 2,3-dimethyl-2-pentanol, n-hexanol, n-heptanol,2-heptanol, n-octanol, n-decanol, s-amyl alcohol, t-amyl alcohol,isoamyl alcohol, 2-ethyl-1-butanol, lauryl alcohol, hexyl decanol, andoleyl alcohol.

Specific examples of the polyhydric alcohols and their derivativesinclude ethylene glycol, ethylene glycol monoacetate, ethylene glycoldimethyl ether, diethylene glycol, diethylene glycol dimethyl ether,diethylene glycol monoacetate, propylene glycol, propylene glycolmonoacetate, propylene glycol monomethyl ether (PGME), propylene glycolmonoethyl ether, propylene glycol monopropyl ether, propylene glycolmonobutyl ether, propylene glycol monomethyl ether acetate (PGMEA), andmonomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether,and monophenyl ether of dipropylene glycol or dipropylene glycolmonoacetate.

Specific examples of the ethers include diethyl ether, diisopropylether, tetrahydrofuran, dioxane, and anisole.

Specific examples of the esters include methyl lactate, ethyl lactate(EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate,ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate, andγ-butyrolactone.

Examples of the aromatic solvents include xylene and toluene.

Examples of the fluorine solvents include chlorofluorocarbons,hydrochlorofluorocarbons, perfluoro compounds, and hexafluoroisopropylalcohol.

Other solvents such as terpene-based petroleum naphtha solvents andparaffinic solvents, which are high-boiling-point weak solvents, canalso be used to improve coating properties.

Of these, preferably, the solvent is at least one selected from thegroup consisting of methyl ethyl ketone, cyclohexanone, methyl isoamylketone, 2-heptanone, ethylene glycol, ethylene glycol dimethyl ether,ethylene glycol monoacetate, diethylene glycol, diethylene glycolmonoacetate, diethylene glycol dimethyl ether, propylene glycol,propylene glycol monoacetate, propylene glycol monomethyl ether (PGME),propylene glycol monomethyl ether acetate (PGMEA), dipropylene glycol,dipropylene glycol monoacetate monomethyl ether, dipropylene glycolmonoacetate monoethyl ether, dipropylene glycol monoacetate monopropylether, dipropylene glycol monoacetate monobutyl ether, dipropyleneglycol monoacetate monophenyl ether, 1,4-dioxane, methyl lactate, ethyllactate, methyl acetate, ethyl acetate, butyl acetate, methylmethoxypropionate, ethyl ethoxypropionate, γ-butyrolactone, andhexafluoroisopropyl alcohol. More preferred are methyl ethyl ketone,propylene glycol monomethyl ether acetate (PGMEA), propylene glycolmonomethyl ether (PGME), cyclohexanone, ethyl lactate, butyl acetate,and γ-butyrolactone.

The amount of the solvent in the photosensitive resin compositionaccording to the second embodiment of the present disclosure is usually50 mass % or more and 2000 mass % or less, preferably 100 mass % or moreand 1000 mass % or less, relative to the concentration (100 mass %) ofthe fluororesin (when the photosensitive resin composition contains thelater-described alkali-soluble resin, the concentration is the sumincluding the alkali-soluble resin). The thickness of the resultingresin film can be adjusted by adjusting the amount of the solvent. Whenthe amount is in the above ranges, the resulting resin film has athickness particularly suitable to obtain banks for organic EL.

In the photosensitive resin composition according to the secondembodiment of the present disclosure, any photopolymerization initiatorcan be used as long as it polymerizes the monomers having apolymerizable double bond exemplified in the description of the methodof producing a fluororesin by electromagnetic waves or electron beams,and any known photopolymerization initiator can be used.

The photopolymerization initiator can be a photo-radical initiator or aphotoacid initiator. These may be used alone or may be used incombination with a photo-radical initiator and a photoacid initiator.Two or more photo-radical initiators or photoacid initiators may bemixed. Use of the photopolymerization initiator in combination withadditives enables living polymerization in some cases. Known additivescan be used.

Specifically, the photo-radical initiators can be classified into thefollowing types, for example: the intramolecular cleavage type thatcleaves the intermolecular bond by absorption of electromagnetic wavesor electron beams to generate radicals; and the hydrogen extraction typethat, when used in combination with a hydrogen donor such as a tertiaryamine or ether, generates radicals. Either type can be used. Aphoto-radical initiator of a type different from those described abovecan also be used.

Specific examples of the photo-radical initiators includebenzophenone-based, acetophenone-based, diketone-based, acylphosphineoxide-based, quinone-based, and acyloin-based photo-radical initiators.

Specific examples of the benzophenone-based photo-radical initiatorsinclude benzophenone, 4-hydroxybenzophenone, 2-benzoylbenzoic acid,4-benzoylbenzoic acid, 4,4′-bis(dimethylamino)benzophenone, and4,4′-bis(diethylamino)benzophenone. Preferred of these are2-benzoylbenzoic acid, 4-benzoylbenzoic acid, and4,4′-bis(diethylamino)benzophenone.

Specific examples of the acetophenone-based photo-radical initiatorsinclude acetophenone, 2-(4-toluenesulfonyloxy)-2-phenylacetophenone,p-dimethylaminoacetophenone, 2,2′-dimethoxy-2-phenylacetophenone,p-methoxyacetophenone,2-methyl-[4-(methylthio)phenyl]-2-morphorino-1-propanone, and2-benzyl-2-dimethylamino-1-(4-morphorinophenyl)-butan-1-one. Preferredof these are p-dimethylaminoacetophenone and p-methoxyacetophenone.

Specific examples of the diketone-based photo-radical initiators include4,4′-dimethoxybenzyl, methyl benzoylformate, and9,10-phenanthrenequinone. Preferred of these are 4,4′-dimethoxybenzyland methyl benzoylformate.

Specific examples of the acylphosphine oxide-based photo-radicalinitiators include bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide.

Specific examples of the quinone-based photo-radical initiators includeanthraquinone, 2-ethylanthraquinone, camphorquinone, and1,4-naphthoquinone. Preferred of these are camphorquinone and1,4-naphthoquinone.

Specific examples of the acyloin-based photo-radical initiators includebenzoin, benzoin methyl ether, benzoin ethyl ether, and benzoinisopropyl ether. Preferred of these are benzoin and benzoin methylether.

Preferred are benzophenone-based, acetophenone-based, and diketone-basedphoto-radical initiators. More preferred are benzophenone-basedphoto-radical initiators.

Examples of preferred commercially available photo-radical initiatorsinclude Irgacure 127, Irgacure 184, Irgacure 369, Irgacure 651, Irgacure819, Irgacure 907, Irgacure 2959, Irgacure OXE-01, Darocur 1173, andLucirin TPO (trade names) available from BASF. More preferred of theseare Irgacure 651 and Irgacure 369.

Specifically, the photoacid initiator is an onium salt of a pair ofcation and anion, the cation being at least one selected from the groupconsisting of aromatic sulfonic acid, aromatic iodonium, aromaticdiazonium, aromatic ammonium, thianthrenium, thioxanthonium, and(2,4-cyclopentadien-1-yl) (1-methylethylbenzene)-iron, the anion beingat least one selected from the group consisting of tetrafluoroborate,hexafluorophosphate, hexafluoroantimonate, and pentafluorophenyl borate.

Particularly preferred of these arebis[4-(diphenylsulfonio)phenyl]sulfide bishexafluorophosphate,bis[4-(diphenylsulfonio)phenyl]sulfidetetrakis(pentafluorophenyl)borate, and diphenyliodoniumhexafluorophosphate.

Examples of commercially available photoacid generators includeCPI-100P, CPI-110P, CPI-101A, CPI-200K, and CPI-210S (trade names)available from San-Apro Ltd.; CYRACURE Photoinitiator UVI-6990, CYRACUREPhotoinitiator UVI-6992, and CYRACURE Photoinitiator UVI-6976 (tradenames) available from Dow Chemical Japan Limited; ADECA OPTOMER SP-150,ADECA OPTOMER SP-152, ADECA OPTOMER SP-170, ADECA OPTOMER SP-172, andADECA OPTOMER SP-300 (trade names) available from ADEKA; CI-5102 andCI-2855 (trade names) available from Nippon Soda Co., Ltd.; SAN AIDSI-60L, SAN AID SI-80L, SAN AID SI-100L, SAN AID SI-110L, SAN AIDSI-180L, SAN AID SI-110, and SAN AID SI-180 (trade names) available fromSanshin Chemical Industry Co. Ltd; Esacure 1064 and Esacure 1187 (tradenames) available from Lamberti; and Irgacure 250 (trade name) availablefrom Ciba Specialty Chemicals.

The amount of the photopolymerization initiator in the photosensitiveresin composition according to the second embodiment of the presentdisclosure is 0.1 mass % or more and 30 mass % or less, preferably 1mass % or more and 20 mass % or less, relative to 100 mass % of thefluororesin (when the photosensitive resin composition contains thelater-described alkali-soluble resin, the concentration is the sumincluding the alkali-soluble resin). When the amount of thephotopolymerization initiator is less than 0.1 mass %, the crosslinkingeffect tends to be insufficient. When the amount thereof is more than 30mass %, the resolution and sensitivity tend to be low.

Preferably, the photosensitive resin composition according to the secondembodiment of the present disclosure essentially contains thefluororesin according to the second embodiment of the presentdisclosure, a solvent, and a photopolymerization initiator, and furthercontains a crosslinking agent (a) and an alkali-soluble resin (b).

The photosensitive resin composition may further contain, for example, anaphthoquinonediazide group-containing compound (c), a basic compound(d), and other additives (e), if necessary.

(a) Crosslinking Agent

The crosslinking agent reacts with a repeating unit represented by theformula (2-2), whereby the resin can have a crosslinked structure. Thiscan improve the mechanical strength of the resulting film.

A known crosslinking agent can be used. Specific examples thereofinclude compounds obtained by reacting an amino group-containingcompound such as melamine, acetoguanamine, benzoguanamine, urea,ethylene urea, propylene urea, or glycoluril with formaldehyde orformaldehyde and a lower alcohol, and substituting a hydrogen atom ofthe amino group by a hydroxymethyl group or a lower alkoxymethyl group;polyfunctional epoxy compounds; polyfunctional oxetane compounds;polyfunctional isocyanate compounds; and polyfunctional acrylatecompounds. Here, those that use melamine are referred to asmelamine-based crosslinking agents, those that use urea are referred toas urea-based crosslinking agents, those that use alkylene urea suchethylene urea or propylene urea are referred to as alkylene urea-basedcrosslinking agents, and those that use glycoluril are referred to asglycoluril-based crosslinking agents. These crosslinking agents may beused alone or in combination of two or more thereof.

Preferably, the crosslinking agent is at least one selected from thesecrosslinking agents. Particularly preferred are glycoluril-basedcrosslinking agents and polyfunctional acrylate compounds.

Examples of the melamine-based crosslinking agents includehexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethylmelamine, and hexabutoxybutyl melamine. Preferred of these ishexamethoxymethyl melamine.

Examples of the urea-based crosslinking agents includebismethoxymethylurea, bisethoxymethylurea, bispropoxymethylurea, andbisbutoxymethylurea. Preferred of these is bismethoxymethylurea.

Examples of the alkylene urea-based crosslinking agents include ethyleneurea-based crosslinking agents such as mono- and/or di-hydroxymethylatedethylene urea, mono- and/or di-methoxymethylated ethylene urea, mono-and/or di-ethoxymethylated ethylene urea, mono- and/ordi-propoxymethylated ethylene urea, and mono- and/or di-butoxymethylatedethylene urea; propylene urea-based crosslinking agents such as mono-and/or di-hydroxymethylated propylene urea, mono- and/ordi-methoxymethylated propylene urea, mono- and/or di-ethoxymethylatedpropylene urea, mono- and/or di-propoxymethylated propylene urea, andmono- and/or di-butoxymethylated propylene urea;1,3-di(methoxymethyl)-4,5-dihydroxy-2-imidazolidinone; and1,3-di(methoxymethyl)-4,5-dimethoxy-2-imidazolidinone.

Examples of the glycoluril-based crosslinking agents include mono-, di-,tri-, and/or tetra-hydroxymethylated glycoluril; mono-, di-, tri-,and/or tetra-methoxymethylated glycoluril; mono-, di-, tri-, and/ortetra-ethoxymethylated glycoluril; mono-, di-, tri-, and/ortetra-propoxymethylated glycoluril; and mono-, di-, tri-, and/ortetra-butoxymethylated glycoluril.

Examples of the polyfunctional acrylate compounds include polyfunctionalacrylates (e.g., A-TMM-3, A-TMM-3L, A-TMM-3LM-N, A-TMPT, and AD-TMP(trade names) available from Shin-Nakamura Chemical Co., Ltd.);polyethylene glycol diacrylates (e.g., A-200, A-400, and A-600 (tradenames) available from Shin-Nakamura Chemical Co., Ltd.); urethaneacrylates (e.g., UA-122P, UA-4HA, UA-6HA, UA-6LPA, UA-11003H, UA-53H,UA-4200, UA-200PA, UA-33H, UA-7100, and UA-7200 (trade names) availablefrom Shin-Nakamura Chemical Co., Ltd.); and pentaerythritoltetraacrylate.

The following are examples of preferred polyfunctional acrylatecompounds.

The amount of the crosslinking agent in the photosensitive resincomposition according to the second embodiment of the present disclosureis 10 mass % or more and 300 mass % or less, preferably 50 mass % ormore and 200 mass % or less, relative to 100 mass % of the fluororesin(when the photosensitive resin composition contains the later-describedalkali-soluble resin, the concentration is the sum including thealkali-soluble resin). When the amount of the crosslinking agent is lessthan 10 mass %, the crosslinking effect tends to be insufficient. Whenthe amount thereof is more than 300 mass %, the resolution andsensitivity tend to be low.

(b) Alkali-Soluble Resin

The alkali-soluble resin has an effect of improving the shape of banksobtainable from the photosensitive resin composition according to thesecond embodiment of the present disclosure, thus providing onepreferred embodiment.

Examples of the alkali-soluble resin include alkali-soluble novolacresins. Alkali-soluble novolac resins can be obtained by condensation ofphenol with aldehyde in the presence of an acid catalyst.

Specific examples of the phenol include phenol, o-cresol, m-cresol,p-cresol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol,3,4-dimethylphenol, 3,5-dimethylphenol, 2,3,5-trimethylphenol,3,4,5-trimethylphenol, resorcinol, 2-methylresorcinol,4-ethylresorcinol, hydroquinone, methylhydroquinone, catechol,4-methyl-catechol, pyrogallol, phloroglucinol, thymol, and isothymol.These phenols may be used alone or in combination of two or morethereof.

Specific examples of the aldehyde include formaldehyde, trioxane,paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde,phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde,o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde,o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde,nitrobenzaldehyde, furfural, glyoxal, glutaraldehyde,terephthalaldehyde, and isophthalaldehyde.

Specific examples of the acid catalyst include hydrochloric acid, nitricacid, sulfuric acid, phosphoric acid, phosphorous acid, formic acid,oxalic acid, acetic acid, methanesulfonic acid, diethyl sulfate, andp-toluenesulfonic acid. These acid catalysts may be used alone or incombination of two or more thereof.

Other examples of the alkali-soluble resin include acid-modified epoxyacrylic resins. Examples of commercially available acid-modified epoxyacrylic resins include CCR-1218H, CCR-1159H, CCR-1222H, CCR-1291H,CCR-1235, PCR-1050, TCR-1335H, UXE-3024, ZAR-1035, ZAR-2001H, ZFR-1185,and ZCR-1569H (trade names) available from Nippon Kayaku Co., Ltd.

The weight average molecular weight of the alkali-soluble resin ispreferably 1000 to 50000 in terms of developability and resolution ofthe photosensitive resin composition.

The amount of the alkali-soluble resin in the photosensitive resincomposition according to the second embodiment of the present disclosureis 500 mass % or more and 10000 mass % or less, preferably 1000 mass %or more and 7000 mass % or less, relative to 100 mass % of thefluororesin. When the amount of the alkali-soluble resin is more than10000 mass %, the fluororesin according to the second embodiment of thepresent disclosure tends to have insufficient ink repellency afterUV-ozone treatment or oxygen plasma treatment.

(c) Naphthoquinonediazide Group-Containing Compound

Any naphthoquinonediazide group-containing compound can be used, and onecommonly used as a photosensitive component of a resist composition fori-rays can be used. The naphthoquinonediazide group-containing compoundhas an effect of improving the shape of banks obtainable from thephotosensitive resin composition according to the second embodiment ofthe present disclosure, thus providing one preferred embodiment.

Specific examples of the naphthoquinonediazide group-containingcompounds include a naphthoquinone-1,2-diazide-4-sulfonate compound, anaphthoquinone-1,2-diazide-5-sulfonate compound, anaphthoquinone-1,2-diazide-6-sulfonate compound, anaphthoquinone-1,2-diazide sulfonate compound, anorthobenzoquinonediazide sulfonate compound, and anorthoanthraquinonediazide sulfonate compound. Preferred of these are anaphthoquinone-1,2-diazide-4-sulfonate compound, anaphthoquinone-1,2-diazide-5-sulfonate compound, and anaphthoquinone-1,2-diazide-6-sulfonate compound, because they haveexcellent solubility. These compounds may be used alone or incombination of two or more thereof.

The amount of the naphthoquinonediazide group-containing compound in thephotosensitive resin composition according to the second embodiment ofthe present disclosure is usually 10 mass % to 60 mass %, preferably 20mass % to 50 mass %, relative to 100 mass % of the fluororesin (when thephotosensitive resin composition contains the above-describedalkali-soluble resin, the concentration is the sum including thealkali-soluble resin). When the amount thereof is more than 60 wt %, thephotosensitive resin composition tends to lack sensitivity.

(d) Basic Compound

The basic compound functions to decrease the diffusion rate of an acidgenerated by the photoacid generator when the acid is diffused into afilm. The presence of the basic compound is likely to improve the shapeof banks by adjusting the acid diffusion distance and increase thestability to obtain a bank shape with desired accuracy even when thebanks formed are left to stand for a long time before being exposed.

Examples of the basic compound include aliphatic amines, aromaticamines, heterocyclic amines, and aliphatic polycyclic amines. Preferredof these are aliphatic amines. Specific examples thereof includesecondary or tertiary aliphatic amines and alkyl alcohol amines. Thesebasic compounds may be used alone or in combination of two or morethereof.

Examples of the aliphatic amines include alkylamines and alkyl alcoholamines each in which at least one hydrogen atom of ammonia (NH₃) issubstituted by a C12 or lower alkyl group or a hydroxyalkyl group.Specific examples thereof include trimethylamine, triethylamine,tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine,tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine,tri-n-decanylamine, tri-n-dodecylamine, dimethylamine, diethylamine,di-n-propylamine, di-n-butylamine, di-n-pentylamine, di-n-hexylamine,di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decanylamine,di-n-dodecylamine, dicyclohexylamine, methylamine, ethylamine,n-propylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine,n-octylamine, n-nonylamine, n-decanylamine, n-dodecylamine,diethanolamine, triethanolamine, diisopropanolamine,triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine.Preferred of these are dialkylamine, trialkylamine, and alkyl alcoholamines. More preferred are alkyl alcohol amines. Particularly preferredof these alkyl alcohol amines are triethanolamine andtriisopropanolamine.

Examples of the aromatic amines and heterocyclic amines include anilineand aniline derivatives such as N-methylaniline, N-ethylaniline,N-propylaniline, N,N-dimethylaniline, 2-methylaniline, 3-methylaniline,4-methylaniline, ethylaniline, propylaniline, trimethylaniline,2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline,2,6-dinitroaniline, 3,5-dinitroaniline, and N,N-dimethyltoluidine;heterocyclic amines such as 1,5-diazabicyclo[4.3.0]non-5-en,1,8-diazabicyclo[5.4.0]undec-7-en, 1,4-diazabicyclo[2.2.2]octane,pyridine, bipyridine, 4-dimethylaminopyridine, hexamethylenetetramine,and 4,4-dimethylimidazoline; hindered amines such asbis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate; alcoholicnitrogen-containing compounds such as 2-hydroxypyridine, aminocresol,2,4-quinolinediol, 3-indolemethanol hydrate, monoethanolamine,diethanolamine, triethanolamine, N-ethyldiethanolamine,N,N-diethylethanolamine, triisopropanolamine, 2,2′-iminodiethanol,2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol,4-(2-hydroxyethyl)morpholine, 2-(2-hydroxyethyl)pyridine,1-(2-hydroxyethyl)piperazine, and1-[2-(2-hydroxyethoxy)ethyl]piperazine; and amines such as picoline,lutidine, pyrrole, piperidine, piperazine, indole, andhexamethylenetetramine.

The amount of the basic compound in the photosensitive resin compositionaccording to the second embodiment of the present disclosure is usually0.001 mass % to 2 mass %, preferably 0.01 mass % to 1 mass %, relativeto 100 mass % of the fluororesin (when the photosensitive resincomposition contains the above-described alkali-soluble resin, theconcentration is the sum including the alkali-soluble resin). When theamount of the basic compound is less than 0.001 mass %, the effectthereof as an additive tends to be insufficient. When the amount thereofis more than 2 mass %, the resolution and sensitivity tend to be low.

(e) Other Additives

The photosensitive resin composition according to the second embodimentof the present disclosure may contain other additives if necessary.Known additives may be suitably used as the other additives, andexamples thereof include various additives such as dissolutioninhibitors, plasticizers, stabilizers, colorants, surfactants,thickeners, leveling agents, defoamers, compatibility agents, adhesives,and antioxidants.

Preferably, the surfactant contains any one or more of fluorine-basedsurfactants and silicone-based surfactants (fluorine-based surfactants,silicone-based surfactants, and surfactants containing both fluorineatoms and silicon atoms).

The fluororesin film according to the second embodiment of the presentdisclosure contains a repeating unit represented by the formula (2-1)and a repeating unit represented by the formula (2-2A). Specifically,the fluororesin film according to the second embodiment of the presentdisclosure is obtained by curing the photosensitive resin compositiondescribed above.

In the formula (2-1), R²⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group; R²⁻² represents a hydrogen atom or a C1-C6 linear,C3-C6 branched, or C3-C6 cyclic alkyl group; R²⁻³ and R²⁻⁴ eachindependently represent a fluorine atom, a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, or a C1-C10 linear, C3-C10branched, or C3-C10 cyclic fluoroalkyl group; and one or more of R²⁻¹,R²⁻³, and R²⁻⁴ are fluorine atoms or the fluoroalkyl groups.

In the formula (2-2A), R²⁻⁵ and R²⁻⁶ each independently represent ahydrogen atom or a methyl group; W² is a divalent linking group andrepresents —O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—,or —C(═O)—NH—; A² is a divalent linking group and represents a C1-C10linear, C3-C10 branched, or C3-C10 cyclic alkylene group in which one ormore hydrogen atoms in the alkylene group may be substituted by hydroxygroups or —O—C(═O)—CH₃; Y² is a divalent linking group and represents—O— or —NH—; and n represents an integer of 1 to 3.

Examples of preferred structures of the repeating unit represented bythe formula (2-1) may include those described in the description of therepeating unit represented by the above formula (2-1).

The repeating unit represented by the formula (2-2A) is formed bycleavage of the polymerizable double bond of the repeating unitrepresented by the formula (2-2). No structural changes occur and theoriginal structure is maintained, except for the changes in thepolymerizable double bond during polymerization. Thus, in the repeatingunit represented by the formula (2-2A), R²⁻⁵, R²⁻⁶, W², A², Y², and nare the same as R²⁻⁵, R²⁻⁶, W², A², Y², and n in the repeating unitrepresented by the formula (2-2), respectively. Examples of specificsubstituents may include those described for the repeating unitrepresented by the above formula (2-2). Examples of preferred structuresof the repeating unit represented by the formula (2-2A) may include thepreferred structures described in the description of the repeating unitrepresented by the formula (2-2), except that they are formed bycleavage of the polymerizable double bond.

The fluororesin film according to the second embodiment of the presentdisclosure can be suitably used as a simple film not having a pattern.It can also be suitably used as a film having a pattern, i.e., banks(described later). Herein, the term “fluororesin film” refers to a filmnot having a pattern.

The fluororesin film according to the second embodiment of the presentdisclosure has excellent water repellency and oil repellency owing toits low surface free energy. For example, the fluororesin film can beused as a water- and oil-repellent agent for treating fabrics (basematerials) for clothes or the like, or a sealing agent for protectingsubstrates (base materials) for microfabricated semiconductors. Thefluororesin film can be used as a film to protect base materials invarious applications.

When forming a fluororesin film, it is particularly preferred that thephotosensitive resin composition essentially contains a fluororesin, asolvent, and a photopolymerization initiator and further contains acrosslinking agent. The photosensitive resin composition may containother additives if necessary. Examples of the solvent, thephotopolymerization initiator, the crosslinking agent, and the otheradditives may include those described above in the description of thephotosensitive resin composition.

When pursuing properties other than the ink repellency of thefluororesin according to the second embodiment of the present disclosureafter UV-ozone treatment or oxygen plasma treatment, the fluororesin ismixed (blended) with other resins, whereby characteristics of otherresins can be incorporated.

The types of monomers of such “other resins” are not limited. Examplesthereof include styrene compounds, acrylic acid esters, and methacrylicacid esters. These may be homopolymers of one type or copolymers of twoor more types. Fluorine-free monomers are particularly preferred.

When forming a fluororesin film by mixing the fluororesin with the“other resins” as described above, the mass % of the fluororesinaccording to the second embodiment of the present disclosure relative to100 mass % of the fluororesin film is usually 50 mass % to 99 mass %,more preferably 60 mass % to 99 mass %, particularly preferably 70 mass% to 99 mass %. The rest are the “other resins” or “various additives”described above. When the amount of the fluororesin according to thesecond embodiment of the present disclosure is less than 50 mass %, theink repellency tends to decrease after UV-ozone treatment or oxygenplasma treatment.

When forming a fluororesin film, the concentration of the fluororesinrelative to 100 mass % of the photosensitive resin composition ispreferably 1 mass % or more and 30 mass % or less, more preferably 2mass % or more and 20 mass % or less, to facilitate coating and filmformation.

A technique similar to conventionally known coating methods can beappropriately used as the method of forming a film using thephotosensitive resin composition according to the second embodiment ofthe present disclosure. A suitable method can be selected according to acoating target. For example, the fluororesin according to the secondembodiment of the present disclosure can be suitably applied with anappropriate coating device such as a slit coater, die coater, gravurecoater, dip coater, or spin coater. A method such as immersion coating,spray coating, or roller coating can also be used.

After a fluororesin film is applied to a substrate, preferably, thesolvent contained in the photosensitive resin composition is dried andremoved from the fluororesin film.

The solvent can be removed by heating the substrate coated with thefluororesin film at 80° C. or higher and 300° C. or lower. Preferably,the heating is performed until a decrease in weight of the fluororesinfilm is no longer observed. The heating may be performed underatmospheric pressure, increased pressure, or reduced pressure. Further,the heating may be performed in air or inert atmospheres, or may beperformed under flow of a predetermined gas.

When the heating temperature is lower than 80° C., the solvent tends toremain. When the heating temperature is higher than 300° C., thefluororesin tends to decompose. More preferably, the heating temperatureis 100° C. or higher and 250° C. or lower, so that the solvent can beremoved without causing decomposition of the fluororesin.

The coating target may be a substrate for a microfabricatedsemiconductor or a fabric for clothes or the like.

Here, the fluororesin film to be formed on a base material may be formedon the entire or partial surface of the base material.

Preferably, the thickness of the resulting fluororesin film is 1 μm ormore and 500 μm or less. A fluororesin film thinner than 1 μm may havelow mechanical strength. A fluororesin film thicker than 500 μm tendsnot to be flat due to large recesses and protrusions on its surface.

The banks according to the second embodiment of the present disclosurecontain a repeating unit represented by the formula (2-1) and arepeating unit represented by the formula (2-2A). Specifically, thebanks according to the second embodiment of the present disclosure areobtained by curing the photosensitive resin composition described above.

When forming the banks according to the second embodiment of the presentdisclosure, it is particularly preferred that the photosensitive resincomposition essentially contains a fluororesin, a solvent, and aphotopolymerization initiator, and further contains a crosslinking agentand an alkali-soluble resin. The photosensitive resin composition mayfurther contain, for example, a naphthoquinonediazide group-containingcompound (c), a basic compound (d), and other additives (e), ifnecessary.

Examples of the compounds may include those described above in thedescription of the photosensitive resin composition.

A resist pattern formation method of a conventional photoresisttechnique can be used as a method of forming the banks according to thesecond embodiment of the present disclosure. The method of forming thebanks is described below.

The banks can be formed by a film forming step (2-4-1), an exposing step(2-4-2), a developing step (2-4-3), and a UV-ozone treatment or oxygenplasma treatment step (2-4-4). In the film forming step (2-4-1), thephotosensitive resin composition is applied to a substrate to form afilm. In the exposing step (2-4-2), the substrate is irradiated withelectromagnetic waves or electron beams through a photo mask to transfera photo mask pattern to the film. In the developing step (2-4-3), thefilm is developed using a developer to form banks. In the UV-ozonetreatment or oxygen plasma treatment step (2-4-4), the residual organicmatter or the like in recesses between the banks is removed.Subsequently, a heating step (2-4-5) may be included if necessary.

Each step is described below with examples.

2-4-1. Film Forming Step

The film forming step is a step of forming a film on a substrate such asa silicon wafer by applying the photosensitive resin composition theretoby spin coating or the like and subsequently heating the silicon waferon a hot plate to remove a solvent. The solvent is removed by heatingusually at a temperature of 60° C. or higher and 200° C. or lower for 10seconds or more and 10 minutes or less, preferably at a temperature of80° C. or higher and 150° C. or lower for 30 seconds or more and 2minutes or less.

The substrate may be a silicon wafer, metal, glass, ITO substrate, orthe like. The substrate may include an organic or inorganic film formedthereon in advance. For example, the substrate may include ananti-reflective film and/or a multilayer resist underlayer, and such afilm and/or underlayer may have a pattern formed thereon. The substratemay be pre-washed. For example, the substrate may be washed withultrapure water, acetone, an alcohol (methanol, ethanol, or isopropylalcohol), or the like.

2-4-2. Exposing Step

The exposing step is a step of setting a desired photo mask in anexposure device, irradiating the film with electromagnetic waves orelectron beams through the photo mask, and then heating the film on ahot plate.

The wavelength of electromagnetic waves or electron beams used forexposure is preferably 100 to 600 nm, more preferably 300 to 500 nm, andthose containing i-rays (365 nm), h-rays (405 nm), and g-rays (436 nm)are particularly preferred. Light with a wavelength of 330 nm or lessmay be cut off if necessary.

Examples of light sources include KrF excimer laser light (wavelength:248 nm), ArF excimer laser light (wavelength: 193 nm), and F2 excimerlaser light (wavelength: 157 nm).

The amount of electromagnetic wave or electron beam exposure is 1 mJ/cm²or more and 200 mJ/cm² or less, preferably 10 mJ/cm² or more and 100mJ/cm² or less.

The heating after exposure is performed on a hot plate usually at atemperature of 60° C. or higher and 150° C. or lower for 10 seconds ormore and 5 minutes or less, preferably at a temperature of 80° C. orhigher and 130° C. or lower for 30 seconds or more and 3 minutes orless.

2-4-3. Developing Step

The developing step is a step of forming banks by dissolving, in adeveloper, the exposed or non-exposed portions of the film obtained inthe exposing step described above.

The developer may be, for example, an alkaline aqueous solution such asa tetramethylammonium hydroxide (TMAH) aqueous solution or atetrabutylammonium hydroxide (TBAH) aqueous solution, or an organicsolvent such as propylene glycol monomethyl ether acetate (PGMEA) orbutyl acetate.

The concentration of the tetramethylammonium hydroxide (TMAH) aqueoussolution is usually 0.1 mass % or more and 5 mass % or less, preferably2 mass % or more and 3 mass % or less.

Any known development method, such as dipping, paddling, or spraying,can be used.

The development time (contact time of the developer with the film) isusually 10 seconds or more and 3 minutes or less, preferably 30 secondsor more and 2 minutes or less.

After development, a step of washing the formed banks film withdeionized water or the like may be included if necessary. The washingmethod and washing time are as described above for the developmentmethod using a developer and development time.

The film after development is subjected to a heating step forcrosslinking and removing low-boiling components. The heating isperformed on a hot plate usually at a temperature of 60° C. or higherand 300° C. or lower for 10 seconds or more and 120 minutes or less,preferably at a temperature of 140° C. or higher and 250° C. or lowerfor 10 minutes or more and 90 minutes or less.

2-4-4. UV-Ozone Treatment or Oxygen Plasma Treatment Step

The UV-ozone treatment or oxygen plasma treatment step is a step ofirradiating the entire surface of the substrate having the banks formedthereon with UV-ozone or oxygen plasma to remove residual organic matteror the like in the recesses between the banks.

The UV-ozone treatment time is usually 10 seconds or more and 30 minutesor less, preferably 1 minute or more and 15 minutes or less.

The oxygen plasma treatment time is usually 10 seconds or more and 30minutes or less, preferably 1 minute or more and 15 minutes or less.

When the UV-ozone treatment or oxygen plasma treatment time is less than10 seconds, removal of residual organic matter tends to be incomplete.When the UV-ozone treatment or oxygen plasma treatment time is more than30 minutes, the thickness of the patterned film tends to decrease.

2-4-5. Heating Step

After the UV-ozone treatment or oxygen plasma treatment step, a heatingstep of heating the resulting banks may be performed if necessary. Thisstep can improve the liquid repellency of the upper surfaces of thebanks according to the second embodiment of the present disclosure.

The heating is performed on a hot plate usually at a temperature of 60°C. or higher and 300° C. or lower for 10 seconds or more and 30120minutes or less, preferably at a temperature of 140° C. or higher and250° C. or lower for 10 minutes or more and 1590 minutes or less.

Preferably, the heat treatment step is performed when the banksaccording to the second embodiment of the present disclosure contain therepeating unit represented by the formula (2-4) wherein B is a carboxygroup. Such banks are one embodiment especially capable of improving theink repellency by the heat treatment step.

The display element according to the second embodiment of the presentdisclosure includes the banks.

Examples of the display element according to the second embodiment ofthe present disclosure include organic electroluminescence displays(hereinafter organic EL displays), micro-LED displays, and quantum dotdisplays.

Examples According to the Second Embodiment

The second embodiment of the present disclosure is described in detailbelow with reference to examples but the present disclosure is notlimited to these examples.

1. Synthesis of Monomers [Synthesis Example 2-1] Synthesis of1,1-bistrifluoromethylbutadiene (BTFBE)

A 1000-ml glass flask equipped with a stirrer was charged withconcentrated sulfuric acid (400 g) and heated to 100° C. Then,1,1,1-trifluoro-2-trifluoromethyl-4-penten-2-ol (a product of CentralGlass Co., Ltd.) (300 g) was gradually dropped thereto over one hour.After dropping, the mixture was stirred at 100° C. for 60 minutes. Noresidual raw materials were detected by ¹⁹F-NMR analysis of the reactionsolution. Then, a fraction at 68° C. to 70° C. was collected byatmospheric distillation from the reaction solution, whereby1,1-bistrifluoromethylbutadiene (hereinafter described as BTFBE) wasobtained (yield: 58%).

<Results of NMR Analysis>

¹H-NMR (solvent: deuterated chloroform; standard substance: TMS); δ(ppm) 5.95 (1H, dd) 6.05 (1H, dd), 6.85 (1H, m), 7.04 (1H, m)

¹⁹F-NMR (solvent: deuterated chloroform; standard substance: C₆D₆); δ(ppm) −65.3 (3F, m), −58.4 (3F, m)

[Synthesis Example 2-2] Synthesis of 4-hydroxystyrene (p-HO-St)

(The synthesis was performed with reference to Examples in JP 2016-98181A.)

A 1000-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with 4-acetoxystyrene (a product of TokyoChemical Industry Co., Ltd., hereinafter described as p-AcO-St) (100 g)and methanol (300 g), which were mixed therein, and1,3,5-trihydroxybenzene (0.50 g; equivalent to 0.5 mass % of p-AcO-St)as a polymerization inhibitor was added to the mixture. Then, after thesolution was cooled to 0° C. in an ice bath, a sodium hydroxide aqueoussolution having a concentration of 12 mass % (corresponding to 1.0equivalent of p-AcO-St) was gradually dropped over 40 minutes, followedby stirring at 0° C. for 30 minutes. No residual raw materials weredetected by ¹H-NMR analysis of the reaction solution. Then, ahydrochloric acid aqueous solution having a concentration of 18 mass %(corresponding to 0.8 equivalents of p-AcO-St) was dropped over 30minutes, followed by stirring for 30 minutes. The pH of the solution wasmeasured to be 6.

The resulting reaction solution was subjected to extraction withmethyl-t-butylether (360 g) at room temperature (about 20° C.), followedby washing twice with purified water (330 g). To the resulting organiclayer was added 1,3,5-trihydroxybenzene in an amount equivalent to 1mass % of 4-hydroxystyrene. Subsequently, 4-hydroxystyrene wasconcentrated to 72 mass %, and added to n-octane (a poor solvent) cooledto 0° C. Then, the solution was placed in an ice bath and stirred forone hour to precipitate crystals of 4-hydroxystyrene. The crystals werefiltered and further washed with n-octane. Then, the crystals werevacuum dried at 25° C. Thus, white crystals of 4-hydroxystyrene(hereinafter described as p-HO-St) were obtained (yield: 66%).

2. Production of Fluororesin (First Step: Polymerization) [Measurementof Molar Ratio of Repeating Units] NMR

The molar ratio of the repeating units of the polymer was determinedfrom the measurements of ¹H-NMR, ¹⁹F-NMR, or ¹³C-NMR.

[Measurement of Polymer Molecular Weight] GPC

The weight average molecular weight Mw and the molecular weightdistribution (Mw/Mn: ratio of the weight average molecular weight Mw tothe number average molecular weight Mn) of the polymer were measured bya high-speed gel permeation chromatograph (hereinafter sometimesreferred to as GPC; model: HLC-8320 GPC available from TosohCorporation) with an ALPHA-M column and an ALPHA-2500 column (productsboth available from Tosoh Corporation) connected in series, usingtetrahydrofuran (THF) as a developing solvent. A refractive indexdifference detector was used.

2-1. Polymerization of Fluororesin Precursors [Polymerization ofFluororesin Precursor 2-1]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with BTFBE obtained in Synthesis Example 2-1(9.5 g (0.05 mol)), p-HO-St obtained in Synthesis Example 2-2 (12.2 g(0.1 mol)), 2-(perfluorohexyl)ethyl methacrylate (a product of TokyoChemical Industry Co., Ltd., hereinafter described as MA-C6F) (43.2 g(0.1 mol)), and MEK (65 g). Then, 2,2′-azobis(2-methylbutyronitrile) (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asAIBN) (1.6 g (0.005 mol)) was added thereto, followed by degassing withstirring. Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 75° C. for reaction for sixhours. n-Heptane (350 g) was dropped into the reaction system, whereby atransparent viscous substance was precipitated. This viscous substancewas isolated by decantation. Vacuum drying was performed at 60° C. Thus,a fluororesin precursor 2-1 as a transparent viscous substance wasobtained (58 g; yield: 90%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor2-1 was as follows: BTFBE repeating unit:p-HO-St repeating unit:MA-C6Frepeating unit=21:51:28.

<Results of GPC Measurement> Mw=12000, Mw/Mn=1.4 [Polymerization ofFluororesin Precursor 2-2]

The same procedure as in the synthesis of the fluororesin precursor 2-1was performed, except that p-HO-St was replaced by vinyl benzoic acid (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asVBA) Thus, a fluororesin precursor 2-2 containing the followingrepeating units was obtained (yield: 87%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor2-2 was as follows: BTFBE repeating unit:VBA repeating unit:MA-C6Frepeating unit=16:57:27.

<Results of GPC Measurement> Mw=9000, Mw/Mn=1.4 [Polymerization ofFluororesin Precursor 2-3]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with BTFBE (9.5 g (0.05 mol)), p-HO-St (6.1 g(0.05 mol)), VBA (7.4 g (0.05 mol)), MA-C6F (43.2 g (0.1 mol)), and MEK(65 g). Then, AIBN (1.6 g (0.010 mol)) was added thereto, followed bydegassing with stirring. Subsequently, the flask was purged withnitrogen gas, and the temperature inside the flask was raised to 75° C.for reaction for six hours. n-Heptane (350 g) was dropped into thereaction system, whereby a white solid was precipitated. The solid wasisolated by filtration and vacuum dried at 60° C., whereby a fluororesinprecursor 2-3 as a white solid was obtained (59 g; yield: 89%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor2-3 was as follows: BTFBE repeating unit:p-HO-St repeating unit:VBArepeating unit:MA-C6F repeating unit=15:25:25:35.

<Results of GPC Measurement> Mw=7500, Mw/Mn=1.3 [Polymerization ofFluororesin Precursor 2-4]

The same procedure as in the synthesis of the fluororesin precursor 2-3was performed, except that p-HO-St was replaced by styrene (a product ofTokyo Chemical Industry Co., Ltd., hereinafter described as St). Thus, afluororesin precursor 2-4 containing the following repeating units wasobtained (yield: 86%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor2-4 was as follows: BTFBE repeating unit:VBA repeating unit:MA-C6Frepeating unit:St repeating unit=16:26:34:24.

<Results of GPC Measurement> Mw=7300, Mw/Mn=1.3 [Polymerization ofFluororesin Precursor 2-5]

The same procedure as in the synthesis of the fluororesin precursor 2-3was performed, except that VBA was replaced by St. Thus, a fluororesinprecursor 2-5 containing the following repeating units was obtained(yield: 84%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor2-5 was as follows: BTFBE repeating unit:p-HO-St repeating unit:MA-C6Frepeating unit:St repeating unit=16:25:35:25.

<Results of GPC Measurement> Mw=6900, Mw/Mn=1.3 [Polymerization ofFluororesin Precursor 2-6]

The same procedure as in the synthesis of the fluororesin precursor 2-3was performed, except that VBA was replaced by p-AcO-St. Thus, afluororesin precursor 2-6 containing the following repeating units wasobtained (yield: 88%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor2-6 was as follows: BTFBE repeating unit:p-HO-St repeating unit:MA-C6Frepeating unit:p-AcO-St repeating unit=17:23:33:27.

<Results of GPC Measurement> Mw=7900, Mw/Mn=1.4 2-2. Polymerization ofComparative Fluororesins [Polymerization of Comparative FluororesinPrecursor 2-1]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with methacrylic acid (a product of TokyoChemical Industry Co., Ltd., hereinafter described as MAA) (17.32 g (0.2mol)), MA-C6F (43.2 g (0.1 mol)), hexafluoroisopropyl methacrylate (aproduct of Central Glass Co., Ltd., hereinafter described as HFIP-M)(23.6 g (0.1 mol)), and MEK (84 g). Then, AIBN (1.6 g (0.010 mol)) wasadded thereto, followed by degassing with stirring. Subsequently, theflask was purged with nitrogen gas, and the temperature inside the flaskwas raised to 80° C., followed by reaction for six hours. The reactionsolution after the reaction was dropped into n-heptane (500 g), wherebya white precipitate was obtained. The precipitate was filtered andvacuum dried at 60° C., whereby a comparative fluororesin precursor 2-1as a white solid was obtained (55 g; yield: 64%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 2-1 was as follows: MA-C6F repeating unit:HFIP-M repeatingunit:MAA repeating unit=20:26:54.

<Results of GPC Measurement> Mw=9700, Mw/Mn=1.5 [Polymerization ofComparative Fluororesin Precursor 2-2]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature with MA-C6F (43.2 g (0.1 mol)), HFIP-M (23.6 g (0.1 mol)),MAA (8.66 g (0.1 mol)), 2-hydroxyethyl methacrylate (a product of TokyoChemical Industry Co., Ltd., hereinafter described as HEMA) (13.01 g(0.1 mol)), and MEK (88 g). Then, AIBN (1.6 g (0.010 mol) was addedthereto, followed by degassing with stirring. Subsequently, the flaskwas purged with nitrogen gas, and the temperature inside the flask wasraised to 80° C., followed by reaction for six hours. The reactionsolution after the reaction was dropped into n-heptane (500 g), wherebya white precipitate was obtained. The precipitate was filtered andvacuum dried at 60° C., whereby a comparative fluororesin precursor 2-2as a white solid was obtained (60 g; yield: 68%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 2-2 was as follows: MA-C6F repeating unit:HFIP-M repeatingunit:MAA repeating unit:HEMA repeating unit=24:26:26:24.

<Results of GPC Measurement> Mw=10700, Mw/Mn=1.5 [Polymerization ofComparative Fluororesin Precursor 2-3]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature with p-HO-St (12.2 g (0.10 mol)), MA-C6F (43.2 g (0.1 mol)),and MEK (55 g). Then, AIBN 1.6 g (0.010 mol) was added thereto, followedby degassing with stirring. Subsequently, the flask was purged withnitrogen gas, and the temperature inside the flask was raised to 80° C.,followed by reaction for six hours. The reaction solution after thereaction was dropped into n-heptane (500 g), whereby a white precipitatewas obtained. The precipitate was filtered and vacuum dried at 60° C.,whereby a comparative fluororesin precursor 2-3 as a white solid wasobtained (45 g; yield: 81%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 2-3 was as follows: p-HO-St repeating unit:MA-C6F repeatingunit=55:45.

<Results of GPC Measurement> Mw=15700, Mw/Mn=1.7 [Polymerization ofComparative Fluororesin Precursor 2-4]

The same procedure as in the synthesis of the comparative fluororesinprecursor 2-3 was performed, except that p-HO-St was replaced by VBA.Thus, a comparative fluororesin precursor 2-4 containing the followingrepeating units was obtained (yield: 88%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 2-4 was as follows: VBA repeating unit:MA-C6F repeatingunit=57:43.

<Results of GPC Measurement> Mw=16300, Mw/Mn=1.7

Table 2-1 shows the repeating units of the resulting fluororesinprecursors 2-1 to 2-6 and comparative fluororesin precursors 2-1 to 2-4,molar ratio of the repeating units, and weight average molecular weight(Mw), molecular weight distribution (Mw/Mn), and yield of each of thefluororesin precursors and comparative fluororesin precursors.

TABLE 2-1 Composition (repeating units) (mol %) Molecular weight PolymerFormula (2-1) Formula (2-2b) Formula (2-3) Formula (2-4) Other Mw Mw/MnYield (%) Fluororesin BTFBE p-HO-St MA-C6F — — 12,000 1.4 90 precursor2-1 21 51 28 Fluororesin BTFBE VBA MA-C6F — — 9,000 1.4 87 precursor 2-216 57 27 Fluororesin BTFBE p-HO-St MA-C6F — — 7,500 1.3 89 precursor 2-315 25 35 VBA 25 Fluororesin BTFBE VBA MA-C6F St — 7,300 1.3 86 precursor2-4 16 26 34 24 Fluororesin BTFBE p-HO-St MA-C6F St — 6,900 1.3 84precursor 2-5 16 25 35 25 Fluororesin BTFBE p-HO-St MA-C6F p-AcO-St —7,900 1.4 88 precursor 2-6 17 23 33 27 Comparative — — MA-C6F — MAA9,700 1.5 64 fluororesin 26 54 precursor 2-1 HFIP-M 20 Comparative — —MA-C6F — MAA 10,700 1.5 68 fluororesin 24 26 precursor 2-2 HFIP-M HEMA26 24 Comparative — p-HO-St MA-C6F — — 15,700 1.7 81 fluororesin 55 45precursor 2-3 Comparative — VBA MA-C6F — — 16,300 1.7 88 fluororesin 5743 precursor 2-4

3. Production of Fluororesin (Second Step: Addition Reaction orCondensation Reaction)

The fluororesin precursors 2-1 to 2-6 and comparative fluororesinprecursors 2-1 to 2-4 obtained in “2. Production of fluororesin (firststep: polymerization)” were each reacted with an acrylic acidderivative, whereby fluororesins were synthesized. The acrylic acidderivative was KarenzAOI, KarenzBEI (products of Showa Denko K.K.), orglycidyl acrylate (a product of Tokyo Chemical Industry Co., Ltd.). Thisreaction is an addition reaction or a condensation reaction of hydroxygroups or carboxylic acid sites of each fluororesin precursor and theacrylic acid derivative.

Described below are fluororesin synthesis examples. The resultingfluororesins were named as follows. The first number represents thenumber of the fluororesin precursor. The subsequent alphabet letterrepresents the acrylic acid derivative used. KarenzAOI is represented by“A”, KarenzBEI is represented by “B”, and glycidyl acrylate isrepresented by “G”. The last number in the parenthesis indicates thenominal amount of acrylic acid derivative introduced (molar ratio)relative to the resin precursor.

[Synthesis of Fluororesin 2-1-A (50)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 2-1 (130 g) (hydroxy equivalent: 0.270 mol) andPGMEA (260 g). Then, KarenzAOI (19 g (0.135 mol)) and triethylamine(5.32 g (0.0528 mol)) were added thereto, and a reaction was carried outat room temperature for four hours. After completion of the reaction,the reaction solution was concentrated, and n-heptane (1500 g) was thenadded to obtain a precipitate. The precipitate was filtered and vacuumdried at 40° C., whereby a fluororesin 2-1-A (50) as a white solid wasobtained (140 g; yield: 94%).

<Results of NMR Measurement>

In the fluororesin 2-1-A (50), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 57:43. Theratio of the repeating units (BTFBE repeating unit and MA-C6F repeatingunit) that do not react with a crosslinking group site was found to beunchanged from that in the fluororesin precursor 2-1 used (i.e., same asbefore the introduction of the crosslinking group). The newly formedbond (W² in the formula (2-2)) was “—O—C(═O)—NH—”.

[Synthesis of Fluororesin 2-1-A (100)]

The same procedure as in the synthesis of the fluororesin 2-1-A (50) wasperformed, except that KarenzAOI was used in an amount of 38 g (0.270mol). Thus, a fluororesin 2-1-A (100) containing the following repeatingunits was obtained (yield: 96%).

<Results of NMR Measurement>

In the fluororesin 2-1-A (100), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 95:5. Theratio of the repeating units (BTFBE repeating unit and MA-C6F repeatingunit) that do not react with a crosslinking group site was found to beunchanged from that in the fluororesin precursor 2-1 used (i.e., same asbefore the introduction of the crosslinking group). The newly formedbond (W² in the formula (2-2)) was “—O—C(═O)—NH—”.

[Synthesis of Fluororesin 2-1-B (50)]

The same procedure as in the synthesis of the fluororesin 2-1-A (50) wasperformed, except that KarenzAOI was replaced by KarenzBEI (32 g (0.134mol)). Thus, a fluororesin 2-1-B (50) containing the following repeatingunits was obtained (yield: 93%).

<Results of NMR Measurement>

In the fluororesin 2-1-B (50), the molar ratio of the amount ofKarenzBEI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 53:47. Theratio of the repeating units (BTFBE repeating unit and MA-C6F repeatingunit) that do not react with a crosslinking group site was found to beunchanged from that in the fluororesin precursor 2-1 used (i.e., same asbefore the introduction of the crosslinking group). The newly formedbond (W² in the formula (2-2)) was “—O—C(═O)—NH—”.

[Synthesis of Fluororesin 2-1-G (50)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 2-1 (130 g) (hydroxy equivalent: 0.270 mol) andPGMEA (260 g). Then, glycidyl acrylate (17 g (0.132 mol)) was addedthereto, and a reaction was carried out at 80° C. for 18 hours. Thecontent after the reaction was concentrated, and heptane (1500 g) wasthen added to obtain a precipitate. The precipitate was filtered andvacuum dried at 40° C., whereby a fluororesin 2-1-G (50) as a whitesolid was obtained (135 g; yield: 92%).

<Results of NMR Measurement>

In the fluororesin 2-1-G, the molar ratio of the amount of glycidylacrylate-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 55:45.

The ratio of the repeating units (BTFBE repeating unit and MA-C6Frepeating unit) that do not react with a crosslinking group site wasfound to be unchanged from that in the fluororesin precursor 2-1 used(i.e., same as before the introduction of the crosslinking group). Thenewly formed bond (W² in the formula (2-2)) was “—O—”.

[Synthesis of Fluororesin 2-2-A (10)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 2-2 (130 g (hydroxy equivalent: 0.355 mol)) andPGMEA (300 g). Then, KarenzAOI (10 g (0.071 mol)) was added thereto, anda reaction was carried out at 60° C. for 18 hours. After completion ofthe reaction, the reaction solution was concentrated, and n-heptane(1500 g) was then added to obtain a precipitate. The precipitate wasfiltered and vacuum dried at 40° C., whereby a fluororesin 2-2-A (10) asa white solid was obtained (132 g; yield: 94%).

<Results of NMR Measurement>

In the fluororesin 2-2-A (10), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 10:90. Theratio of the repeating units (BTFBE repeating unit and MA-C6F repeatingunit) that do not react with a crosslinking group site was found to beunchanged from that in the fluororesin precursor 2-1 used (i.e., same asbefore the introduction of the crosslinking group). The newly formedbond (W² in the formula (2-2)) was “—C(═O)—NH—”.

[Synthesis of Fluororesins 2-2-B (5) to 2-6-G (50)]

Fluororesins 2-2-B (5) to 2-6-G (50) were produced as in the fluororesin2-1-A (50), 2-1-A (100), 2-1-G (50), or 2-2-A (10). Table 2-2 shows thefluororesin precursors used, acrylic acid derivative, crosslinking groupstructure formed (W² in the formula (2-2)), amount of crosslinkinggroups introduced (reaction rate), and amount of residual hydroxy groups(non-reaction rate).

[Synthesis of Comparative Fluororesins 2-1-A (50) to 2-4-G (50)]

Comparative fluororesins 2-1-A (50) to 2-4-G (50) were produced as inthe fluororesins 2-1-A (50), 2-1-A (100), 2-1-G (50), or 2-2-A (10).Table 2-3 shows the comparative fluororesin precursors used, type of thecrosslinking group site introduced, amount of crosslinking groupsintroduced (reaction rate), and amount of residual hydroxy groups(non-reaction rate).

TABLE 2-2 Ratio of acrylic acid derivative introduced (mol %)Fluororesin Acrylic acid Amount of acrylic Fluororesin precursorderivative Formed bond acid derivative Amount of residual Molecularweight No. No. Formula (2-2c) (W² in formula (2-2)) introduced hydroxygroups Mw Mw/Mn 2-1-A (50) 2-1 A —O—C(═O)—NH— 57 43 13,500 1.4 2-1-A(100) 2-1 A —O—C(═O)—NH— 95 5 15,000 1.4 2-1-B (50) 2-1 B —O—C(═O)—NH—55 45 14,000 1.4 2-1-G (50) 2-1 G —O— 47 53 13,500 1.4 2-2-A (10) 2-2 A—C(═O)—NH— 10 90 9,300 1.3 2-2-B (5) 2-2 B —C(═O)—NH— 5 95 9,200 1.32-2-G (50) 2-2 G —C(═O)—O— 47 53 10,500 1.3 2-3-A (50) 2-3 A—O—C(═O)—NH— 52 48 9,000 1.3 —C(═O)—NH— 2-3-B (40) 2-3 B —O—C(═O)—NH— 4258 9,300 1.3 —C(═O)—NH— 2-3-G (50) 2-3 G —O— 46 54 9,000 1.3 —C(═O)—O—2-4-A (10) 2-4 A —C(═O)—NH— 9 91 7,600 1.3 2-4-B (5) 2-4 B —C(═O)—NH— 496 7,500 1.3 2-4-G (50) 2-4 G —C(═O)—O— 48 52 8,800 1.3 2-5-A (50) 2-5 A—O—C(═O)—NH— 54 46 8,400 1.3 2-5-B (45) 2-5 B —O—C(═O)—NH— 43 57 8,9001.3 2-5-G (50) 2-5 G —O— 47 53 8,400 1.3 2-6-A (50) 2-6 A —O—C(═O)—NH—53 47 9,400 1.4 2-6-B (40) 2-6 B —O—C(═O)—NH— 38 52 9,600 1.4 2-6-G (50)2-6 G —O— 46 54 9,400 1.4

TABLE 2-3 Ratio of acrylic acid derivative introduced (mol %)Comparative Acrylic acid Amount of acrylic Comparative fluororesinderivative Formed bond acid derivative Amount of residual Molecularweight fluororesin No. precursor No. Formula (2-2c) (W² in formula(2-2)) introduced hydroxy groups Mw Mw/Mn Comparative Comparative A—C(═O)—NH— 51 49 10,200 1.5 2-1-A (50) 2-1 Comparative Comparative B—C(═O)—NH— 54 46 10,700 1.5 2-1-B (50) 2-1 Comparative Comparative G—C(═O)—O— 53 47 10,200 1.5 2-1-G (50) 2-1 Comparative Comparative A—O—C(═O)—NH— 48 52 12,200 1.5 2-2-A (50) 2-2 —C(═O)—NH— ComparativeComparative B —O—C(═O)—NH— 43 57 12,700 1.5 2-2-B (45) 2-2 —C(═O)—NH—Comparative Comparative G —O— 51 49 12,200 1.5 2-2-G (50) 2-2 —C(═O)—O—Comparative Comparative A —C(═O)—NH— 52 48 17,200 1.7 2-3-A (50) 2-3Comparative Comparative B —C(═O)—NH— 42 58 17,700 1.7 2-3-B (40) 2-3Comparative Comparative G —O— 46 54 17,200 1.7 2-3-G (50) 2-3Comparative Comparative A —C(═O)—NH— 8 92 16,600 1.7 2-4-A (10) 2-4Comparative Comparative B —C(═O)—NH— 5 95 16,500 1.7 2-4-B (5) 2-4Comparative Comparative G —C(═O)—O— 51 49 18,500 1.7 2-4-G (50) 2-4

4. Preparation of Photosensitive Resin Compositions [Preparation ofPhotosensitive Resin Compositions 2-1 to 2-38, ComparativePhotosensitive Resin Compositions 2-1 to 2-12]

The fluororesins or comparative fluororesins produced above, solvents,photopolymerization initiators, crosslinking agents, alkali-solubleresins, naphthoquinonediazide group-containing compounds, and basiccompounds were blended according to Tables 2-4 to 2-6. The resultingsolutions were filtered through a 0.2-μm membrane filter, wherebyphotosensitive resin compositions 2-1 to 2-38 and comparativephotosensitive resin compositions 2-1 to 2-12 were prepared. In thetables, the symbol “-” means no addition of the component.

The following solvents, photopolymerization initiators, crosslinkingagents, alkali-soluble resin, naphthoquinonediazide group-containingcompound, and basic compound were used.

Solvents:

S-1: propylene glycol monomethyl ether acetate (PGMEA); S-2:γ-butyrolactone; S-3: propylene glycol monomethyl ether (PGME); S-4:methyl ethyl ketone; S-5: cyclohexanone; S-6: ethyl lactate; S-7: butylacetate

Photopolymerization Initiators:

Ini-1: 4-benzoylbenzoic acid; Ini-2: Irgacure 651 (a product of BASF);Ini-3: Irgacure 369 (a product of BASF)

Crosslinking Agents:

CL-1: pentaerythritol tetraacrylate (a product of Tokyo ChemicalIndustry Co., Ltd.); CL-2: A-TMM-3 (a product of Shin-Nakamura ChemicalCo., Ltd.)

Alkali-Soluble Resin:

ASP-1: CCR-1235 (a product of Nippon Kayaku Co., Ltd.)

Naphthoquinonediazide Group-Containing Compound:

N-1: naphthoquinone-1,2-diazide-5-sulfonate compound (PC-5, a product ofToyo Gosei Co., Ltd.)

Basic Compound:

B-1: triethanolamine (a product of Tokyo Chemical Industry Co., Ltd.)

TABLE 2-4 Alkali- Naphthoquinonediazide Photopolymerization Crosslinkingsoluble group-containing Photosensitive Fluororesin Solvent initiatoragent resin compound Basic compound resin Parts Parts Parts Parts PartsParts Parts composition by by by by by by by No. Type mass Type massType mass Type mass Type mass Type mass Type mass 2-1  2-1-A (50) 1.0S-1 100 Ini-2 7.5 — — — — — — — — 2-2  2-1-A (50) 1.0 S-1 70 Ini-3 7.5CL-1 50 ASP-1 50 — — — — S-3 30 2-3   2-1-A (100) 1.0 S-2 100 Ini-2 7.5— — — — — — — — 2-4   2-1-A (100) 1.0 S-1 65 Ini-3 5.0 CL-1 30 ASP-1 50— — — — S-3 35 2-5  2-1-B (50) 1.0 S-3 100 Ini-1 7.5 — — — — — — — —2-6  2-1-B (50) 0.5 S-1 60 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — S-3 402-7  2-1-G (50) 1.0 S-4 100 Ini-1 7.5 — — — — — — — — 2-8  2-1-G (50)1.0 S-1 68 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — S-3 32 2-9  2-2-A (10) 1.0S-4 100 Ini-2 7.5 — — — — — — — — 2-10 2-2-A (10) 1.0 S-1 50 Ini-3 7.5CL-1 50 ASP-1 50 — — — — S-3 50 2-11 2-2-B (5)  1.0 S-4 100 Ini-2 7.5 —— — — — — — — 2-12 2-2-B (5)  0.8 S-1 55 Ini-3 7.5 CL-1 50 ASP-1 50 — —— — S-3 45 2-13 2-2-G (50) 1.0 S-4 100 Ini-3 7.5 — — — — — — — — 2-142-2-G (50) 1.0 S-1 60 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — S-3 40 2-152-3-A (50) 1.0 S-4 100 Ini-2 7.5 — — — — — — — — 2-16 2-3-A (50) 1.0 S-170 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — S-3 30 2-17 2-3-B (40) 1.0 S-5 100Ini-2 7.5 — — — — — — — — 2-18 2-3-B (40) 1.5 S-1 70 Ini-3 7.5 CL-1 50ASP-1 45 N-1 10 B-1 0.5 S-3 30 2-19 2-3-G (50) 1.0 S-4 100 Ini-3 7.5 — —— — — — — — 2-20 2-3-G (50) 0.7 S-1 70 Ini-3 7.5 CL-1 65 ASP-1 50 — — —— S-3 30

TABLE 2-5 Naphthoquinonediazide Photopolymerization CrosslinkingAlkali-soluble group-containing Basic Photosensitive Fluororesin Solventinitiator agent resin compound compound resin Parts Parts Parts PartsParts Parts Parts composition by by by by by by by No. Type mass Typemass Type mass Type mass Type mass Type mass Type mass 2-21 2-4-A (10)1.0 S-6 100 Ini-2 7.5 — — — — — — — — 2-22 2-4-A (10) 1.0 S-1 70 Ini-37.5 CL-1 50 ASP-1 50 — — — — S-3 30 2-23 2-4-B (5)  1.0 S-1 100 Ini-27.5 — — — — — — — — 2-24 2-4-B (5)  1.2 S-1 60 Ini-2 7.5 CL-2 70 ASP-140 N-1 10 B-1 0.5 S-3 40 2-25 2-4-G (50) 1.0 S-7 100 Ini-3 7.5 — — — — —— — — 2-26 2-4-G (50) 1.0 S-1 65 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — S-335 2-27 2-5-A (50) 1.0 S-2 100 Ini-2 7.5 — — — — — — — — 2-28 2-5-A (50)1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — S-3 30 2-29 2-5-B (45) 1.0S-8 100 Ini-2 7.5 — — — — — — — — 2-30 2-5-B (45) 1.0 S-1 70 Ini-1 7.5CL-2 30 ASP-1 50 — — — — S-3 30 2-31 2-5-G (50) 1.0 S-2 100 Ini-3 7.5 —— — — — — — — 2-32 2-5-G (50) 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 60 — —— — S-3 30 2-33 2-6-A (50) 1.0 S-1 100 Ini-2 7.5 — — — — — — — — 2-342-6-A (50) 1.0 S-1 70 Ini-3 7.5 CL-1 75 ASP-1 50 — — — — S-3 30 2-352-6-B (40) 1.0 S-1 100 Ini-1 7.5 — — — — — — — — 2-36 2-6-B (40) 1.5 S-7100 Ini-3 7.5 CL-1 50 ASP-1 70 N-1 10 — — 2-37 2-6-G (50) 1.0 S-8 100Ini-3 7.5 — — — — — — — — 2-38 2-6-G (50) 1.3 S-5 100 Ini-2 7.5 CL-2 75ASP-1 50 — — — —

TABLE 2-6 Alkali- Naphthoquinonediazide Comparative ComparativePhotopolymerization Crosslinking soluble group-containing photosensitivefluororesin Solvent initiator agent resin compound Basic compound resinParts Parts Parts Parts Parts Parts Parts composition by by by by by byby No. Type mass Type mass Type mass Type mass Type mass Type mass Typemass 2-1 Comparative 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — 2-1-A(50) S-3 30 2-2 Comparative 1.0 S-3 100 Ini-1 7.5 CL-1 50 ASP-1 50 — — —— 2-1-B (50) 2-3 Comparative 1.0 S-4 100 Ini-1 7.5 CL-1 50 ASP-1 50 — —— — 2-1-G (50) 2-4 Comparative 1.0 S-1 50 Ini-3 7.5 CL-1 50 ASP-1 50 — —— — 2-2-A (50) S-3 50 2-5 Comparative 1.0 S-1 55 Ini-3 7.5 CL-1 50 ASP-150 N-1 10 B-1 0.5 2-2-B (45) S-3 45 2-6 Comparative 1.0 S-7 100 Ini-37.5 CL-1 50 ASP-1 50 — — — — 2-2-G (50) 2-7 Comparative 1.0 S-1 70 Ini-37.5 CL-1 50 ASP-1 50 — — — — 2-3-A (50) S-3 30 2-8 Comparative 1.0 S-170 Ini-3 7.5 CL-1 50 ASP-1 50 — — B-1 0.5 2-3-B (40) S-3 30 2-9Comparative 1.0 S-1 100 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — 2-3-G (50) 2-10 Comparative 1.0 S-1 100 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — 2-4-A(10)  2-11 Comparative 1.0 S-1 60 Ini-2 7.5 CL-2 50 ASP-1 50 — — B-1 0.52-4-B (5)  S-3 40  2-12 Comparative 1.0 S-1 60 Ini-3 7.5 CL-1 50 ASP-150 — — — — 2-4-G (50) S-3 40

5. Evaluation of Resistance of Fluororesin Film to UV-Ozone Treatmentand Liquid Repellency [Formation of Fluororesin Films 2-1 to 2-38 andComparative Fluororesin Films 2-1 to 2-12]

The photosensitive resin compositions 2-1 to 2-38 and comparativephotosensitive resin compositions 2-1 to 2-12 prepared were each appliedto a silicon wafer using a spin coater at a rotation speed of 1000 rpm.Subsequently, these resin compositions were heated on a hot plate at100° C. for 150 seconds, whereby fluororesin films 2-1 to 2-38 andcomparative fluororesin films 2-1 to 2-12 (the numbers correspond to therespective numbers of the photosensitive resin compositions) were eachformed on the silicon wafer.

The fluororesin films 2-2, 2-10, 2-16, 2-22, 2-28, and 2-34 and thecomparative fluororesin films 2-1, 2-4, 2-7, and 2-10 obtained abovewere subjected to contact angle measurement with respect to water,anisole, and methyl benzoate before and after UV-ozone treatment andafter heating. Water, anisole, and methyl benzoate were used as inksolvents.

[UV-Ozone Treatment Step and Heating Step]

The fluororesin films and comparative fluororesin films on the siliconwafer were each subjected to UV-ozone treatment for 10 minutes using aUV-ozone treatment device (available from Sen Lights Corporation; modelnumber: PL17-110). Subsequently, heating was performed at 230° C. for 60seconds.

[Contact Angle Measurement]

With a contact angle meter “DMs-601” available from Kyowa InterfaceScience Co., Ltd., each fluororesin film surface and each comparativefluororesin film surface were subjected to contact angle measurementwith respect to water, anisole, and methyl benzoate before and after theUV-ozone treatment and after the subsequent heating step.

[Film Thickness Measurement]

Using a stylus-type surface shape measuring instrument “Dektak-8”available from Bruker Nano, the thickness of each of the fluororesinfilms and comparative fluororesin films was measured before and afterthe UV-ozone treatment and after the subsequent heating step.

[Measurement of Molecular Weight Changes]

The fluororesin films and the comparative fluororesin films were eachscraped off with a spatula, and each resulting solid was dissolved inTHF to determine the molecular weight by GPC before and after theUV-ozone treatment and after the subsequent heating step. The tablesshow each molecular weight in the cases where multiple peaks weredetected. In addition, “1000, multiple” in the table indicates the caseswhere multiple peaks were detected and the molecular weight was 1000 orless.

Table 2-7 shows the results of the contact angle measurement in eachstep. Table 2-8 shows the results of the film thickness measurement andmolecular weight in each step.

TABLE 2-7 Contact angle (°) Anisole Methyl benzoate Water PhotosensitiveUV-ozone After UV-ozone After UV-ozone After Fluororesin resin treatmentheating treatment heating treatment heating film No. composition No.Before After step Before After step Before After step 2-2  2-2  70 55 6868 52 64 105 98 104 2-10 2-10 72 40 69 71 38 68 106 97 105 2-16 2-16 7048 68 71 43 69 104 96 103 2-22 2-22 71 45 67 72 34 68 105 97 104 2-282-28 69 50 67 68 44 68 105 97 104 2-34 2-34 67 54 66 68 51 66 104 96 104Comparative Comparative 77 47 46 74 32 28 106 33 21 2-1  2-1 Comparative Comparative 75 43 45 75 31 27 107 37 25 2-4  2-4 Comparative Comparative 72 42 46 70 40 31 109 50 63 2-7  2-7 Comparative Comparative 73 37 48 71 28 27 110 31 58 2-10 2-10

TABLE 2-8 Photosensitive Film thickness (nm) Molecular weight resinUV-ozone After UV-ozone After Fluororesin composition treatment heatingtreatment heating film No. No. Before After step Before After step 2-2 2-2  1800 1710 1660 12,000 11,300  10,900  2-10 2-10 1810 1720 16809,000 8,600 8,500 2-16 2-16 1900 1790 1720 7,500 7,200 7,100 2-22 2-221850 1760 1690 7,300 7,100 7,000 2-28 2-28 1950 1830 1790 6,900 6,7006,600 2-34 2-34 1920 1810 1740 7,900 7,700 7,500 Comparative Comparative1820 420 <100 9,700 <1000 <1000 2-1  2-1  multiple multiple ComparativeComparative 1900 510 230 10,700 <1000 <1000 2-4  2-4  multiple multipleComparative Comparative 1810 850 610 15,700 4000, 4100, 2-7  2-7  <1000<1000 multiple multiple Comparative Comparative 1730 720 490 16,3005200, 4800, 2-10 2-10 <1000 <1000 multiple multiple

According to the results in Table 2-7, in the fluororesin films 2-2,2-10, 2-16, 2-22, 2-28, and 2-34 according to the second embodiment ofthe present disclosure, although a decrease in contact angle wasobserved after the UV-ozone treatment, the contact angle increased to adegree comparable to that before the UV-ozone treatment due to thesubsequent heat treatment step, indicating good liquid repellency of thefluororesin films after the UV-ozone treatment. In contrast, in thecomparative fluororesin films 2-1, 2-4, 2-7, and 2-10, although a highcontact angle was observed before the UV-ozone treatment, the contactangle decreased after the UV-ozone treatment and remained small evenafter the subsequent heating step, indicating insufficient liquidrepellency after the UV-ozone treatment.

According to the results in Table 2-8, in the fluororesin films 2-2,2-10, 2-16, 2-22, 2-28, and 2-34 according to the second embodiment ofthe present disclosure, although a slight decrease in film thickness wasobserved after the UV-ozone treatment, the molecular weight of theremaining film was comparable, indicating excellent resistance to theUV-ozone treatment. In contrast, in the comparative fluororesin films2-1, 2-4, 2-7, and 2-10, a significant decrease in film thickness wasconfirmed after the UV-ozone treatment, and the molecular weight of theremaining film significantly decreased as compared to that before theUV-ozone treatment, indicating insufficient resistance to the UV-ozonetreatment.

6. Evaluation of Liquid Repellency on Upper Surfaces of Banks afterUV-Ozone Treatment or Oxygen Plasma Treatment

The photosensitive resin compositions 2-2, 2-6, 2-8, 2-10, 2-14, 2-16,and 2-26 and the comparative photosensitive resin compositions 2-1, 2-4,2-7, and 2-12 obtained in “4. Preparation of photosensitive resincompositions” were used to form banks 2-2, 2-6, 2-8, 2-10, 2-14, 2-16,and 2-26 and comparative banks 2-1, 2-4, 2-7, and 2-12, respectively,and the bank properties were evaluated and compared. Table 2-9 shows theresults. The components used for the above photosensitive resincompositions except for the fluororesin or comparative fluororesin werestandardized to compare the properties.

[Formation of Banks]

A 10-cm square ITO substrate was washed with ultrapure water and thenacetone. Subsequently, the substrate was subjected to UV-ozone treatmentfor five minutes using the UV-ozone treatment described above. Then, thephotosensitive resin compositions 2-2, 2-6, 2-8, 2-10, 2-14, 2-16, and2-26 and the comparative photosensitive resin compositions 2-1, 2-4,2-7, and 2-12 obtained in “4. Preparation of photosensitive resincompositions” were each applied to the UV-ozone-treated substrate usinga spin coater at a rotation speed of 1000 rpm, followed by heating on ahot plate at 100° C. for 150 seconds. Thus, fluororesin films andcomparative fluororesin films each having a thickness of 2 μm wereformed.

Each resulting resin film was exposed to i-rays (wavelength: 365 nm)using a mask aligner (a product of SUSS MicroTec Group) with a maskhaving a 5-μm line-and-space pattern.

The resulting resin film after exposure was subjected to evaluation ofsolubility in a developer, evaluation of bank properties (sensitivityand resolution), and contact angle measurement.

[Solubility in Developer]

The resin film on the ITO substrate after exposure was immersed in analkali developer at room temperature for 80 seconds to evaluate thesolubility in the alkali developer. The alkali developer was a 2.38 mass% tetramethylammonium hydroxide aqueous solution (hereinafter sometimesreferred to as TMAH). The solubility of the banks was evaluated bymeasuring the thickness of the banks after immersion using a contactfilm thickness meter. The banks were were evaluated as “soluble” whencompletely dissolved, and “insoluble” when the resist film remainedundissolved.

[Bank Properties (Sensitivity and Resolution)]

The optimal exposure Eop (mJ/cm²) for forming banks arranged in theline-and-space pattern was determined and used as an index forsensitivity.

The resulting pattern of banks was observed under a scanning electronmicroscope to evaluate the resolution. A pattern without visibleline-edge roughness was evaluated as “excellent”; a pattern withslightly visible line-edge roughness was evaluated as “good”; and apattern with significant line-edge roughness was evaluated as “poor”.

[Contact Angle]

Each substrate having the banks obtained in the above step was heated at230° C. for 60 minutes. Then, the entire substrate surface was subjectedto UV-ozone treatment or oxygen plasma treatment for 10 minutes.Subsequently, heating was performed at 230° C. for 60 seconds. Thecontact angle between the bank or comparative surface and anisole wasmeasured before and after the UV-ozone treatment and after thesubsequent heating step.

The UV-ozone treatment device and the contact angle meter describedabove were used. An oxygen plasma treatment device was Plasma DryCleaner PDC-210 available from Yamato Scientific Co., Ltd. The oxygenplasma treatment was performed at an oxygen gas flow rate of 30 cc/minand an output of 300 W.

TABLE 2-9 Banks 2-2 2-6 2-8 2-10 2-14 2-16 Comparative photosensitiveresin composition 2-2 2-6 2-8 2-10 2-14 2-16 Solubility in Non-exposedportion Soluble Soluble Soluble Soluble Soluble Soluble developerExposed portion Insoluble Insoluble Insoluble Insoluble InsolubleInsoluble Resist properties Sensitivity (mJ/cm²) 105  100  102  100 100  102  Resolution Excellent Excellent Excellent Excellent ExcellentExcellent Contact angle (°) Before UV-ozone treatment 35 37 32 28 36 38Non-exposed After UV-ozone treatment 10 10 10 10 10 10 portion Afterheating step 10 10 10 10 10 10 Contact angle (°) Before UV-ozonetreatment 70 71 70 72 71 70 Exposed portion After UV-ozone treatment 5456 53 38 36 47 After heating step 68 66 67 71 70 68 Contact angle (°)Before oxygen plasma treatment 33 34 29 25 33 35 Non-exposed Afteroxygen plasma treatment 10 10 10 10 10 10 portion After heating step 1010 10 10 10 10 Contact angle (°) Before oxygen plasma treatment 70 71 7072 71 70 Exposed portion After oxygen plasma treatment 41 46 43 31 28 40After heating step 67 65 68 70 71 68 Comparative Comparative ComparativeComparative Banks 2-26 2-1 2-4 2-7 2-12 Comparative photosensitive resincomposition 2-26 Comparative Comparative Comparative Comparative 2-1 2-42-7 2-12 Solubility in Non-exposed portion Soluble Soluble SolubleSoluble Soluble developer Exposed portion Insoluble Insoluble InsolubleInsoluble Insoluble Resist properties Sensitivity (mJ/cm²) 105  105 102  100  102  Resolution Excellent Excellent Excellent ExcellentExcellent Contact angle (°) Before UV-ozone treatment 40 40 38 38 36Non-exposed After UV-ozone treatment 10 10 10 10 10 portion Afterheating step 10 10 10 10 10 Contact angle (°) Before UV-ozone treatment69 75 74 72 73 Exposed portion After UV-ozone treatment 45 47 43 40 35After heating step 67 35 33 29 36 Contact angle (°) Before oxygen plasmatreatment 37 38 35 35 33 Non-exposed After oxygen plasma treatment 10 1010 10 10 portion After heating step 10 10 10 10 10 Contact angle (°)Before oxygen plasma treatment 69 75 74 72 73 Exposed portion Afteroxygen plasma treatment 36 35 33 36 28 After heating step 68 25 27 25 26

As shown in Table 2-9, the evaluation of solubility in the developershows that the banks according to the second embodiment of the presentdisclosure and the comparative banks were made of a negative resist inwhich only the non-exposed portions are soluble. The evaluation of thebank properties shows that all the banks had comparable sensitivity and“excellent” resolution in which the 5-μm line-and-space pattern of themask was transferred with good resolution without visible line-edgeroughness. Specifically, these evaluations show that the fluororesinaccording to the second embodiment of the present disclosure and thecomparative fluororesins only slightly influenced the banks.

In contrast, in the banks according to the second embodiment of thepresent disclosure, although the contact angle between the exposedportions (corresponding to the upper surfaces of the banks) and anisoledecreased due to the UV-ozone treatment or oxygen plasma treatment, thecontact angle increased due to the subsequent heating step, indicatinggood liquid repellency. In the comparative banks, the contact angledecreased due to the UV-ozone treatment or oxygen plasma treatment andremained small even after the subsequent heating step, indicatinginsufficient liquid repellency.

Third Embodiment

A third embodiment of the present disclosure is described below in thefollowing order.

3-1. Fluororesin

3-1-1. Repeating unit represented by formula (3-1)3-1-2. Repeating unit represented by formula (3-2)3-1-3. Repeating unit represented by formula (3-3)3-1-4. Repeating unit represented by formula (3-4)3-1-5. Repeating unit represented by formula (3-5)3-1-6. Preferred embodiments of fluororesin3-1-7. Production method of fluororesin3-2. Photosensitive resin composition3-3. Fluororesin film

3-4. Banks

3-5. Display device

3-1. Fluororesin

The fluororesin according to the third embodiment of the presentdisclosure contains a repeating unit represented by a formula (3-1) anda repeating unit represented by a formula (3-2).

In the formula (3-1), R³⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group; R³⁻² represents a hydrogen atom or a C1-C6 linear,C3-C6 branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ eachindependently represent a fluorine atom, a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, or a C1-C10 linear, C3-C10branched, or C3-C10 cyclic fluoroalkyl group; and one or more of R³⁻¹,R³⁻³, and R³⁻⁴ are fluorine atoms or the fluoroalkyl groups.

In the formula (3-2), R³⁻⁵ and R³⁻⁶ each independently represent ahydrogen atom or a methyl group; W³ is a divalent linking group andrepresents —O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—,or —C(═O)—NH—; A³⁻¹ and A³⁻² are divalent linking groups and eachindependently represent a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkylene group in which one or more hydrogen atoms in thealkylene group may be substituted by hydroxy groups or —O—C(═O)—CH₃;Y³⁻¹ and Y³⁻² are divalent linking groups and each independentlyrepresent —O— or —NH—; n represents an integer of 1 to 3; and rrepresents 0 or 1.

The molecular weight of the fluororesin in terms of weight averagemolecular weight measured by gel permeation chromatography (GPC) usingpolystyrene as a standard substance is preferably 1000 or more and1000000 or less, more preferably 2000 or more and 500000 or less,particularly preferably 3000 or more and 100000 or less. When themolecular weight is less than 1000, the resulting fluororesin film orbanks for organic EL tend to have a low strength. When the molecularweight is more than 1000000, it may be difficult to form a fluororesinfilm due to lack of solubility of the fluororesin in solvents.

The dispersity (Mw/Mn) is preferably 1.01 to 5.00, more preferably 1.01to 4.00, particularly preferably 1.01 to 3.00.

The fluororesin may be a random copolymer, an alternating copolymer, ablock copolymer, or a graft copolymer. Preferably, the fluororesin is arandom copolymer to suitably (not locally) disperse characteristics ofeach repeating unit.

The fluororesin may be a polymer containing a combination of one or moretypes of units each corresponding to a repeating unit represented by theformula (3-1) and one or more types of units each corresponding to arepeating unit represented by the formula (3-2) (described later).

The fluororesin may be a mixture (blend) of such polymers.

Preferably, the fluororesin has a fluorine content of 20 mass % or moreand 80 mass % or less relative to 100 mass % of the fluororesin. Thefluororesin having a fluorine content in the above ranges is easilysoluble in solvents. A fluororesin film or banks having excellent liquidrepellency can be obtained because the fluororesin contains fluorineatoms.

3-1-1. Repeating Unit Represented by Formula (3-1)

The following describes the repeating unit represented by the formula(3-1).

In the formula (3-1), R³⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group. A hydrogen atom and a methyl group are preferred.

In the formula (3-1), R³⁻² represents a hydrogen atom or a C1-C6 linear,C3-C6 branched, or C3-C6 cyclic alkyl group.

Examples of R³⁻² include a hydrogen atom, a methyl group, an ethylgroup, an n-propyl group, an isopropyl group, an n-butyl group, a1-methylpropyl group, a 2-methylpropyl group, a tert-butyl group, ann-pentyl group, an isopentyl group, a 1,1-dimethylpropyl group, a1-methylbutyl group, a 1,1-dimethylbutyl group, an n-hexyl group, acyclopentyl group, and a cyclohexyl group. A hydrogen atom, a methylgroup, an ethyl group, an n-propyl group, and an isopropyl group arepreferred. A hydrogen atom and a methyl group are more preferred.

In the formula (3-1), R³⁻³ and R³⁻⁴ each independently represent afluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylgroup, or a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic fluoroalkylgroup.

Further, one or more of R³⁻¹, R³⁻³, and R³⁻⁴ are fluorine atoms or thefluoroalkyl groups.

When R³⁻³ and R³⁻⁴ each independently represent a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, examples thereof include amethyl group, an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, a 1-methylpropyl group, a 2-methylpropyl group, atert-butyl group, an n-pentyl group, an isopentyl group, a1,1-dimethylpropyl group, a 1-methylbutyl group, a 1,1-dimethylbutylgroup, an n-hexyl group, a cyclopentyl group, and a cyclohexyl group. Amethyl group, an ethyl group, an n-propyl group, and an isopropyl groupare preferred.

R³⁻³ and R³⁻⁴ each independently preferably represent a fluorine atom, atrifluoromethyl group, a difluoromethyl group, a pentafluoroethyl group,a 2,2,2-trifluoroethyl group, an n-heptafluoropropyl group, a2,2,3,3,3-pentafluoropropyl group, a 3,3,3-trifluoropropyl group, ahexafluoroisopropyl group, a heptafluoroisopropyl group, ann-nonafluorobutyl group, an isononafluorobutyl group, or atert-nonafluorobutyl group; more preferably a fluorine atom, atrifluoromethyl group, a difluoromethyl group, a pentafluoroethyl group,a 2,2,2-trifluoroethyl group, an n-heptafluoropropyl group, a2,2,3,3,3-pentafluoropropyl group, a 3,3,3-trifluoropropyl group, or ahexafluoroisopropyl group; particularly preferably a fluorine atom, adifluoromethyl group, or a trifluoromethyl group.

The following are examples of preferred structures of the repeating unitrepresented by the formula (3-1).

The amount of the repeating unit represented by the formula (3-1) in thefluororesin is preferably 5 mass % or more and 70 mass % or less, morepreferably 10 mass % or more and 50 mass % or less, particularlypreferably 10 mass % or more and 30 mass % or less, relative to 100 mass% of the fluororesin.

When the amount of the repeating unit represented by the formula (3-1)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents. When the amount of the repeating unit represented by theformula (3-1) is less than 5 mass %, the resistance against UV-ozonetreatment or oxygen plasma treatment tends to decrease.

Depending on use, for example, a method in which the fluororesin isdirectly pressed under heat without being dissolved in solvents (i.e., ahot-press method) can be used to form a fluororesin film. In this case,use of the repeating unit represented by the formula (3-1) in an amountof more than 70 mass % does not result in either poor resistance of thewhole fluororesin to UV-ozone treatment or oxygen plasma treatment orpoor ink repellency after UV-ozone treatment or oxygen plasma treatment,and such use is thus not avoided in the third embodiment of the presentdisclosure.

Here, it is assumed, although not confirmed, that the repeating unitrepresented by the formula (3-1) according to the third embodiment ofthe present disclosure has the following effects. The effects of thethird embodiment of the present disclosure described herein are notintended to be exhaustive.

The repeating unit represented by the formula (3-1) has an effect ofimparting ink repellency to the fluororesin after UV-ozone treatment oroxygen plasma treatment. Preferably, R³⁻³ and R³⁻⁴ are each a fluorineatom or a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic fluoroalkylgroup, because the above effect is particularly high in such a case.

Further, the repeating unit represented by the formula (3-1) has aneffect of increasing the resistance of the fluororesin to UV-ozonetreatment or oxygen plasma treatment. The possible reasons are asfollows.

Generally, the ester bond is considered to be reactive with and not veryresistant to UV-ozone treatment or oxygen plasma treatment (also seecomparative fluororesin films 3-1 to 3-10 and Tables 3-12 to 3-15described later). Thus, in a fluoropolymer consisting of acrylic siteshaving an ester bond adjacent to the main chain, the ester bond becomesa reactive site. Presumably, this results in low resistance of thefluoropolymer to the UV-ozone treatment or oxygen plasma treatment(e.g., fluoropolymers disclosed in Patent Literatures 3 and 4).

In contrast, the repeating unit represented by the formula (3-1)according to the third embodiment of the present disclosure has astructure consisting of hydrocarbons without substituents mainlycontaining oxygen such as an ester bond that is reactive with UV-ozonetreatment or oxygen plasma treatment. Thus, the presence of therepeating unit represented by the formula (3-1) in the resin is presumedto increase the resistance of the fluororesin according to the thirdembodiment of the present disclosure to the UV-ozone treatment or oxygentreatment.

3-1-2. Repeating Unit Represented by Formula (3-2)

The following describes the repeating unit represented by the formula(3-2).

In the formula (3-2), R³⁻⁵ and R³⁻⁶ each independently represent ahydrogen atom or a methyl group.

In the formula (3-2), W³ is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—. —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—.Preferred of these are —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, and —C(═O)—NH—.

The fluororesin according to the third embodiment of the presentdisclosure in which W³ is —O—C(═O)—NH— has better ink repellency afterUV-ozone treatment or oxygen plasma treatment, and is thus oneparticularly preferred embodiment.

In the formula (3-2), A³⁻¹ and A³⁻² are divalent linking groups and eachindependently represent a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkylene group in which one or more hydrogen atoms in thealkylene group may be substituted by hydroxy groups or —O—C(═O)—CH₃.

When the divalent linking groups A³⁻¹ and A³⁻² each independentlyrepresent a C1-C10 linear alkylene group, examples thereof include amethylene group, an ethylene group, a propylene group, an n-butylenegroup, an n-pentylene group, an n-hexalene group, an n-heptalene group,an n-octalene group, an n-nonalene group, and an n-decalene group.

When the divalent linking groups A³⁻¹ and A³⁻² each independentlyrepresent a C3-C10 branched alkylene group, examples thereof include anisopropylene group, an isobutylene group, a sec-butylene group, atert-butylene group, an isopentalene group, and an isohexalene group.

When the divalent linking groups A³⁻¹ and A³⁻² each independentlyrepresent a C3-C10 cyclic alkylene group, examples thereof include acyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclooctyl group, a cyclodecanyl group,and a 4-tert-butylcyclohexyl group.

When one or more hydrogen atoms in these alkylene groups are substitutedby hydroxy groups, examples of these hydroxy group-substituted alkylenegroups include a 1-hydroxyethylene group (—CH(OH)CH₂—), a2-hydroxyethylene group (—CH₂CH(OH)—), a 1-hydroxy-n-propylene group, a2-hydroxy-n-propylene group, a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—), a 1-hydroxy-n-butylene group, a 2-hydroxy-n-butylenegroup, a hydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—), ahydroxy-isobutylene group (—CH₂CH(CH₂OH)CH₂—), and ahydroxy-tert-butylene group (—C(CH₂OH)(CH₃)CH₂—).

When one or more hydrogen atoms in these alkylene groups are substitutedby —O—C(═O)—CH₃, examples of these substituted-alkylene groups includethose in which hydroxy groups of the hydroxy group-substituted alkylenegroups exemplified above are substituted by —O—C(═O)—CH₃.

Preferably, the divalent linking groups A³⁻¹ and A³⁻² each independentlyrepresent a methylene group, an ethylene group, a propylene group, ann-butylene group, an isobutylene group, a sec-butylene group, acyclohexyl group, a 1-hydroxyethylene group (—CH(OH)CH₂—), a2-hydroxyethylene group (—CH₂CH(OH)—), a 2-hydroxy-n-propylene group, ahydroxy-isopropylene group (—CH(CH₂OH)CH₂—), a 2-hydroxy-n-butylenegroup, or a hydroxy-sec-butylene group (—CH(CH₂OH)CH₂CH₂—); morepreferably, an ethylene group, a propylene group, a 1-hydroxyethylenegroup (—CH(OH)CH₂—), a 2-hydroxyethylene group (—CH₂CH(OH)—), a2-hydroxy-n-propylene group, or a hydroxy-isopropylene group(—CH(CH₂OH)CH₂—); particularly preferably an ethylene group, a1-hydroxyethylene group (—CH(OH)CH₂—), or a 2-hydroxyethylene group(—CH₂CH(OH)—).

In the formula (3-2), Y³⁻¹ and Y³⁻² are divalent linking groups and eachindependently represent —O— or —NH—, with —O— being more preferred.

In the formula (3-2), n represents an integer of 1 to 3, with n of 1being particularly preferred.

In the formula (3-2), r represents 0 or 1. When r is 0, (—C(═O)—)represents a single bond.

The following are examples of preferred of structures of the repeatingunit represented by the formula (3-2).

The amount of the repeating unit represented by the formula (3-2) in thefluororesin is preferably 5 mass % or more and 70 mass % or less, morepreferably 10 mass % or more and 50 mass % or less, particularlypreferably 10 mass % or more and 30 mass % or less, relative to 100 mass% of the fluororesin.

When the amount of the repeating unit represented by the formula (3-2)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents. When the amount of the repeating unit represented by theformula (3-1) is less than 5 mass %, a fluororesin film or banksobtainable from the fluororesin tend to have lower adhesion tosubstrates.

Here, it is assumed, although not confirmed, that the repeating unitrepresented by the formula (3-2) according to the third embodiment ofthe present disclosure in the fluororesin has an effect of improving theadhesion of the resulting fluororesin film or banks to substrates. Theeffects of the third embodiment of the present disclosure describedherein are not intended to be exhaustive.

The fluororesin according to the third embodiment of the presentdisclosure may be, as described above, a mixture (blend) of a copolymercontaining a repeating unit represented by the formula (3-1) and arepeating unit represented by the formula (3-2) and another copolymercontaining a repeating unit represented by the formula (3-1) and arepeating unit represented by the formula (3-2). Specifically, in onepreferred third embodiment of the present disclosure, the fluororesinaccording to the third embodiment of the present disclosure is a mixtureof a fluororesin containing a repeating unit represented by the formula(3-2) wherein W³ is —O—C(═O)—NH— and a fluororesin containing arepeating unit represented by the formula (3-2) wherein W³ is—C(═O)—NH—.

3-1-3. Repeating Unit Represented by Formula (3-3)

Preferably, the fluororesin according to the third embodiment of thepresent disclosure further contains a repeating unit represented by aformula (3-3).

The fluororesin may be a polymer containing a combination of a repeatingunit represented by the formula (3-3), a repeating unit represented bythe formula (3-1), and a repeating unit represented by the formula(3-2).

The fluororesin may also be a mixture (blend) of a polymer containing arepeating unit represented by the formula (3-3) and a polymer containinga repeating unit represented by the formula (3-1) and a repeating unitrepresented by the formula (3-2). When the fluororesin is a mixture, thefluororesin may be a mixture of a polymer containing a repeating unitrepresented by the formula (3-3) and a repeating unit represented by theformula (3-1) and a polymer containing a repeating unit represented bythe formula (3-2), or a mixture of a polymer containing a repeating unitrepresented by the formula (3-3) and a repeating unit represented by theformula (3-2) and a polymer containing a repeating unit represented bythe formula (3-1).

In the formula (3-3), R³⁻⁷ represents a hydrogen atom or a methyl group;

In the formula (3-3), R³⁻⁸ represents a C1-C15 linear, C3-C15 branched,or C3-C15 cyclic alkyl group in which one or more hydrogen atoms in thealkyl group are substituted by fluorine atoms; and the repeating unithas a fluorine content of 30 mass % or more.

When R³⁻⁸ is a linear hydrocarbon group, specific examples thereofinclude a methyl group, an ethyl group, a propyl group, a butyl group, apentyl group, a hexyl group, a heptyl group, an octyl group, a nonylgroup, and C10-C14 linear alkyl groups in which one or more hydrogenatoms are substituted by fluorine atoms.

When R³⁻⁸ is a linear hydrocarbon group, preferably, the repeating unitrepresented by the formula (3-3) is a repeating unit represented by thefollowing formula (3-3-1).

wherein R³⁻⁷ is the same as R³⁻⁷ in the formula (3-3); X is a hydrogenatom or a fluorine atom; p is an integer of 1 to 4; and q is an integerof 1 to 14.

In the repeating unit represented by the formula (3-3-1), particularlypreferably, p is an integer of 1 or 2, q is an integer of 2 to 8, and Xis a fluorine atom.

The following are examples of preferred structures of the repeating unitrepresented by the formula (3-3).

The amount of the repeating unit represented by the formula (3-3) ispreferably 5 mass % or more and 70 mass % or less, more preferably 10mass % or more and 50 mass % or less, particularly preferably 10 mass %or more and 30 mass % or less, relative to 100 mass % of thefluororesin.

When the amount of the repeating unit represented by the formula (3-3)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents.

The repeating unit represented by the formula (3-3) is a repeating unitthat imparts ink repellency to the fluororesin after UV-ozone treatmentor oxygen plasma treatment. Thus, when pursuing high ink repellency,preferably, the fluororesin according to the third embodiment of thepresent disclosure contains the repeating unit represented by theformula (3-3).

3-1-4. Repeating Unit Represented by Formula (3-4)

Preferably, the fluororesin according to the third embodiment of thepresent disclosure further contains a repeating unit represented by aformula (3-4).

The fluororesin may be a polymer containing a combination of a repeatingunit represented by the formula (3-4), a repeating unit represented bythe formula (3-1), and a repeating unit represented by the formula(3-2). Alternatively, the fluororesin may be a polymer containing acombination of a repeating unit represented by the formula (3-4), arepeating unit represented by the formula (3-1), a repeating unitrepresented by the formula (3-2), and a repeating unit represented bythe formula (3-3).

The fluororesin may also be a mixture (blend) of a polymer containing arepeating unit represented by the formula (3-4) and a polymer containinga repeating unit represented by the formula (3-1) and a repeating unitrepresented by the formula (3-2). When the fluororesin is a mixture, thefluororesin may be a mixture of a polymer containing a repeating unitrepresented by the formula (3-4) and a repeating unit represented by theformula (3-1) and a polymer containing a repeating unit represented bythe formula (3-2), or a mixture of a polymer containing a repeating unitrepresented by the formula (3-4) and a repeating unit represented by theformula (3-2) and a polymer containing a repeating unit represented bythe formula (3-1). Further, when the fluororesin is a mixture containinga repeating unit represented by the formula (3-3), the fluororesin maybe a mixture of a repeating unit represented by the formula (3-3) andany of the above possible combinations of the repeating unitsrepresented by the formulas (3-1), (3-2), and (3-4).

In the formula (3-4), R³⁻⁵, Y³⁻¹, A³⁻¹, and r are the same as R³⁻⁵,Y³⁻¹, A³⁻¹, and r in the formula (3-2), respectively. Specific orpreferred examples may also include those described in “3-1-2. Repeatingunit represented by formula (3-2)”.

In the formula (3-4), E³⁻¹ represents a hydroxy group, a carboxy group,or an oxirane group.

When E³⁻¹ is an oxirane group, examples thereof include an ethyleneoxide group, a 1,2-propylene oxide group, and a 1,3-propylene oxidegroup. Preferred of these is an ethylene oxide group.

In the formula (3-4), s represents 0 or 1. When s is 0, (—Y³⁻¹-A³⁻¹-)represents a single bond. When r is 0 and s is 0, the structure has E³⁻¹bonded to the main chain of the repeating unit.

The formula (3-4) may be a repeating unit represented by the followingformula (3-6).

In the formula (3-6), R³⁻⁶ and Y³⁻¹ are the same as R³⁻⁶ and Y³⁻¹ in theformula (3-2), respectively.

The following are examples of preferred structures of the repeating unitrepresented by the formula (3-4).

A repeating unit represented by the formula (3-4) wherein E³⁻¹ is ahydroxy group or a carboxy group imparts solubility to the fluororesinin an alkali developer. Thus, when it is desired to impart alkalidevelopability to a film obtainable from the fluororesin, preferably,the fluororesin according to the third embodiment of the presentdisclosure contains the repeating unit represented by the formula (3-4)wherein E³⁻¹ is a hydroxy group or a carboxy group. Specifically, whenit is desired to form banks containing a repeating unit represented bythe formula (3-1) and a repeating unit represented by the formula (3-2A)in the third embodiment of the present disclosure, further adding therepeating unit represented by the formula (3-4) wherein E³⁻¹ is ahydroxy group or a carboxy group tends to improve the shape of theresulting patterned film, thus providing one preferred embodiment.

3-1-5. Repeating Unit Represented by Formula (3-5)

Preferably, the fluororesin according to the third embodiment of thepresent disclosure further contains a repeating unit represented by aformula (3-5).

The fluororesin may be a polymer containing a combination of a repeatingunit represented by the formula (3-5), a repeating unit represented bythe formula (3-1), and a repeating unit represented by the formula(3-2). Alternatively, the fluororesin may be a polymer containing acombination of a repeating unit represented by the formula (3-5), arepeating unit represented by the formula (3-1), a repeating unitrepresented by the formula (3-2), and a repeating unit represented bythe formula (3-3).

The fluororesin may also be a mixture (blend) of a polymer containing arepeating unit represented by the formula (3-5) and a polymer containinga repeating unit represented by the formula (3-1) and a repeating unitrepresented by the formula (3-2). When the fluororesin is a mixture, thefluororesin may be a mixture of a polymer containing a repeating unitrepresented by the formula (3-5) and a repeating unit represented by theformula (3-1) and a polymer containing a repeating unit represented bythe formula (3-2), or a mixture of a polymer containing a repeating unitrepresented by the formula (3-5) and a repeating unit represented by theformula (3-2) and a polymer containing a repeating unit represented bythe formula (3-1). Further, when the fluororesin is a mixture containinga repeating unit represented by the formula (3-3), the fluororesin maybe a mixture of a repeating unit represented by the formula (3-3) andany of the above possible combinations of the repeating unitsrepresented by the formulas (3-1), (3-2), and (3-5).

In the formula (3-5), R³⁻⁹ represents a hydrogen atom or a methyl group.

In the formula (3-5), each B³ independently represents a hydroxy group,a carboxy group, —C(═O)—O—R³⁻¹⁰ (R³⁻¹⁰ represents a C1-C15 linear,C3-C15 branched, or C3-C15 cyclic alkyl group in which one or morehydrogen atoms in the alkyl group are substituted by fluorine atoms, andR³⁻¹⁰ has a fluorine content of 30 mass % or more), or —O—C(═O)—R³⁻¹¹(R³⁻¹¹ represents a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup).

When B³ is —C(═O)—O—R³⁻¹⁰, specific examples of R³⁻¹⁰ may include thoseof R³⁻⁸ in the formula (3-3).

When B³ is —O—C(═O)—R³⁻¹¹, examples of R³⁻¹¹ include a methyl group, anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a1-methylpropyl group, a 2-methylpropyl group, a tert-butyl group, ann-pentyl group, an isopentyl group, a 1,1-dimethylpropyl group, a1-methylbutyl group, a 1,1-dimethylbutyl group, an n-hexyl group, acyclopentyl group, and a cyclohexyl group. A hydrogen atom, a methylgroup, an ethyl group, an n-propyl group, and an isopropyl group arepreferred. A methyl group is more preferred.

In the formula (3-5), m represents an integer of 0 to 3.

The following are examples of preferred structures of the repeating unitrepresented by the formula (3-5).

The amount of the repeating unit represented by the formula (3-5) ispreferably 5 mass % or more and 70 mass % or less, more preferably 10mass % or more and 50 mass % or less, particularly preferably 20 mass %or more and 40 mass % or less, relative to 100 mass % of thefluororesin.

When the amount of the repeating unit represented by the formula (3-5)is more than 70 mass %, the fluororesin tends to be hardly soluble insolvents.

A repeating unit represented by the formula (3-5) wherein B³ is ahydroxy group or a carboxy group imparts solubility to the fluororesinin an alkali developer. Thus, when it is desired to impart alkalidevelopability to a film obtainable from the fluororesin, preferably,the fluororesin according to the third embodiment of the presentdisclosure contains the repeating unit represented by the formula (3-5)wherein B³ is a hydroxy group or a carboxy group. Specifically, when itis desired to form banks containing a repeating unit represented by theformula (3-1) and a repeating unit represented by the formula (3-2A) inthe third embodiment of the present disclosure, further adding therepeating unit represented by the formula (3-5) wherein B³ is a hydroxygroup or a carboxy group tends to improve the shape of the resultingpatterned film, thus providing one preferred embodiment.

3-1-6. Preferred Embodiments of Fluororesin

Particularly preferred embodiments of the fluororesin according to thethird embodiment of the present disclosure may include the following sixembodiments.

Embodiment 3-1

Fluororesin containing a repeating unit represented by the followingformula (3-1) and a repeating unit represented by the following formula(3-2)

Formula (3-1): R³⁻¹ and R³⁻² are hydrogen atoms; and R³⁻³ and R³⁻⁴ areeach independently a fluorine atom, a difluoromethyl group, or atrifluoromethyl group.

Formula (3-2): R³⁻⁵ and R³⁻⁶ are each independently a hydrogen atom or amethyl group; W³ is —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A³⁻¹ and A³⁻² are each independently an ethylene group; Y³⁻¹ and Y³⁻²are —O—; n is 1; and r is 1.

Embodiment 3-2

Fluororesin containing a repeating unit represented by the followingformula (3-1) and a repeating unit represented by the following formula(3-2)Formula (3-1): same as described in Embodiment 3-1Formula (3-2): R³⁻⁵ and R³⁻⁶ are each independently a hydrogen atom or amethyl group; W³ represents —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or—C(═O)—NH—; A³⁻¹ and A³⁻² are each independently an ethylene group, a1-hydroxy-n-ethylene group (—CH(OH)CH₂—), or a 2-hydroxy-n-ethylenegroup (—CH₂CH(OH)—); Y³⁻¹ and Y³⁻² are —O—; n is 1; and r is 1.

Embodiment 3-3

Fluororesin containing a repeating unit represented by the followingformula (3-1) and a repeating unit represented by the following formula(3-2)Formula (3-1): same as described in Embodiment 3-1Formula (3-2): R³⁻⁵ and R³⁻⁶ are each independently a hydrogen atom or amethyl group; W³ represents —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or—C(═O)—NH—; A³⁻¹ and A³⁻² are each independently an ethylene group or abutyl group; Y³⁻¹ and Y³⁻² are —O—; n is 1; and r is 0.

Embodiment 3-4

Fluororesin containing repeating units represented by the followingformulas (3-1), (3-2), and (3-3-1)Formula (3-1): same as described in Embodiment 3-1Formula (3-2): same as described in Embodiment 3-1Formula (3-3-1): R³⁻⁷ is a methyl group; p is 2; q is an integer of 4 to8; X is a fluorine atom.

Embodiment 3-5

Fluororesin containing repeating units represented by the followingformulas (3-1), (3-2), (3-3-1), and (3-4)Formula (3-1): same as described in Embodiment 3-1Formula (3-2): same as described in Embodiment 3-1Formula (3-3-1): same as described in Embodiment 3-4Formula (3-4): R³⁻⁵, Y³⁻¹, A³⁻¹, and r are as the same as described inEmbodiment 1; s is 1; and E³⁻¹ is a hydroxy group or a carboxy group.

Embodiment 3-6

Fluororesin containing repeating units represented by the followingformulas (3-1), (3-2), (3-3-1), (3-4), and (3-5)Formula (3-1): same as described in Embodiment 3-1Formula (3-2): same as described in Embodiment 3-1Formula (3-3-1): same as described in Embodiment 3-4Formula (3-4): same as described in Embodiment 3-5Formula (3-5): R³⁻⁹ is a hydrogen atom; B³ is a hydroxy group, a carboxygroup, or —O—C(═O)—CH₃; and m is 1.

3-1-7. Method of Producing Fluororesin

The fluororesin according to the third embodiment of the presentdisclosure can be easily produced by the following two steps: first,monomers represented by formulas (3-1a) and (3-2a) are polymerized toobtain a fluororesin precursor containing a repeating unit representedby the formula (3-1) and a repeating unit represented by a formula(3-2b); and then the formula (3-2b) between the repeating unitrepresented by the formula (3-1) and the repeating unit represented bythe formula (3-2b) is subjected to addition reaction with an acrylicacid derivative represented by a formula (3-2c).

In the formula (3-1), R³⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group; R³⁻² represents a hydrogen atom or a C1-C6 linear,C3-C6 branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ eachindependently represent a fluorine atom, a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, or a C1-C10 linear, C3-C10branched, or C3-C10 cyclic fluoroalkyl group; and one or more of R³⁻¹,R³⁻³, and R³⁻⁴ are fluorine atoms or the fluoroalkyl groups.

In the formula (3-1a), R³⁻¹, R³⁻², R³⁻³, and R³⁻⁴ are the same as R³⁻¹,R³⁻², R³⁻³, and R³⁻⁴ in the formula (3-1), respectively.

In the formula (3-2), R³⁻⁵ and R³⁻⁶ each independently represent ahydrogen atom or a methyl group; W is a divalent linking group andrepresents —O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—,or —C(═O)—NH—; A³⁻¹ and A³⁻² are divalent linking groups and eachindependently represent a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkylene group in which one or more hydrogen atoms in thealkylene group may be substituted by hydroxy groups or —O—C(═O)—CH₃;Y³⁻¹ and Y³⁻² are divalent linking groups and each independentlyrepresent —O— or —NH—; n represents an integer of 1 to 3; and rrepresents 0 or 1.

In the formula (3-2a), R³⁻⁵, Y³⁻¹, A³⁻¹, and r are the same as R³⁻⁵,Y³⁻¹, A³⁻¹, and r in the formula (3-2), respectively; and E³⁻²represents a hydroxy group or an ethylene oxide group.

In the formula (3-2b), R³⁻⁵, Y³⁻¹, A³⁻¹, r and E³⁻² are the same asR³⁻⁵, Y³⁻¹, A³⁻¹, and r in the formula (3-2) and E³⁻² in the formula(3-2a), respectively.

In the formula (3-2c), R³⁻⁶, Y³⁻², A³⁻², and n are the same as R³⁻⁶,Y³⁻², A³⁻², and n in the formula (3-2), respectively; and Z³ representsan isocyanate group (—N═C═O) or an acid halide (—C(═O)—X, X represents ahalogen atom or an imidazolyl group), an acid anhydride, a halogen atom,a hydroxy group, an amino group (—NH₂), or an oxirane group.

Each step is described below.

[First Step]

In the first step, monomers represented by the formulas (3-1a) and(3-2a) are polymerized to produce a fluororesin precursor containing arepeating unit represented by the formula (3-1) and a repeating unitrepresented by the formula (3-2b).

The monomer represented by the formula (3-1a) may be a commerciallyavailable product or can be prepared by a known method or a method basedthereon. For example, preferably, the monomer is prepared by a methoddescribed in Journal of Organic Chemistry, 1970, Vol. 35, No. 6, pp.2096-2099, or a method based thereon.

The repeating unit represented by the formula (3-1) is formed bycleavage of the polymerizable double bond of the monomer represented bythe formula (3-1a). No structural changes occur and the originalstructure is maintained, except for the changes in the polymerizabledouble bond during polymerization. Thus, in the monomer represented bythe formula (3-1a), R³⁻¹, R³⁻², R³⁻³, and R³⁻⁴ are the same as R³⁻¹,R³⁻², R³⁻³, and R³⁻⁴ in the repeating unit represented by the formula(3-1), respectively. Examples of specific substituents include thosedescribed in “3-1-1. Repeating unit represented by formula (3-1)”.Examples of preferred structures of the monomer represented by theformula (3-1a) may include those of the respective monomers beforecleavage of the polymerizable double bond in the repeating unitsexemplified in “3-1-1. Repeating unit represented by formula (3-1)”.

The monomer represented by the formula (3-2a) may be a commerciallyavailable product or can be prepared by a known method or a method basedthereon. Use of a commercially available product is preferred in termsof easy availability.

The repeating unit represented by the formula (3-2b) is formed bycleavage of the polymerizable double bond of the monomer represented bythe formula (3-2a). No structural changes occur and the originalstructure is maintained, except for the changes in the polymerizabledouble bond during polymerization.

In the monomer represented by the formula (3-2a), E³⁻² represents ahydroxy group or an ethylene oxide group. In the monomer represented bythe formula (3-2a), preferably, R³⁻⁵ is a hydrogen atom or a methylgroup; A³⁻¹ is an ethylene group; Y³⁻¹ is —O—; E³⁻² is a hydroxy group;and r is 0 or 1.

The method of polymerizing the monomers represented by the formulas(3-1a) and (3-2a) is now described.

Any common polymerization method can be used, but radical polymerizationand ionic polymerization are preferred. In some cases, polymerizationmethods such as coordination anionic polymerization, living anionicpolymerization, cationic polymerization, ring-opening metathesispolymerization, vinylene polymerization, and vinyl addition can also beused. Of these, radical polymerization is particularly preferred. Thesepolymerization methods may be known methods. The radical polymerizationmethod is described below, but polymerization can be easily performedalso by other methods according to known documents or the like.

The radical polymerization may be performed in a batch type,semi-continuous type, or continuous-type operation by a knownpolymerization method such as bulk polymerization, solutionpolymerization, suspension polymerization, or emulsion polymerization inthe presence of a radical polymerization initiator or radical initiationsource.

Any radical polymerization initiator may be used. Examples thereofinclude azo compounds, peroxide compounds, persulfate compounds, andredox compounds. Particularly preferred are2,2′-azobis(2-methylbutyronitrile), dimethyl2,2′-azobis(2-methylpropionate), tert-butyl peroxypivalate,di-tert-butyl peroxide, isobutyryl peroxide, lauroyl peroxide, succinicacid peroxide, dicinnamyl peroxide, di-n-propyl peroxydicarbonate,tert-butylperoxyallyl monocarbonate, benzoyl peroxide, hydrogenperoxide, and ammonium persulfate.

Any reaction vessel may be used for polymerization. Preferably,polymerization is performed using a polymerization solvent in additionto the monomers and initiators. A polymerization solvent that does notinterfere with radical polymerization is preferred. Typical examplesthereof include ester solvents such as ethyl acetate and n-butylacetate; ketone solvents such as acetone, methyl ethyl ketone, andmethyl isobutyl ketone; hydrocarbon solvents such as toluene andcyclohexane; and alcohol solvents such as methanol, isopropyl alcohol,and ethylene glycol monomethyl ether. Solvents such as water, chainether solvents, cyclic ether solvents, chlorofluorocarbon solvents, andaromatic solvents can also be used. These polymerization solvents can beused alone or in combination of two or more thereof. A molecular weightmodifier such as mercaptan may also be used in combination. The reactiontemperature for polymerization is suitably changed according to aradical polymerization initiator or radical polymerization initiatingsource. Usually, the reaction temperature is preferably 20° C. to 200°C., more preferably 30° C. to 140° C., particularly preferably 50° C. to120° C.

The polymerization time is usually 0.1 to 48 hours, preferably 1 to 24hours. Preferably, a point at which the monomer is consumed isdetermined, by an analytical instrument such as a high-performanceliquid chromatograph (HPLC) or nuclear magnetic resonance (NMR) device,as the endpoint of the polymerization. After completion of thepolymerization, the reaction can be terminated by cooling thepolymerization solution to room temperature or below.

The monomer concentration relative to 100 mass % of the polymerizationsystem at the beginning of polymerization is preferably 1 mass % or moreand 95 mass % or less, more preferably 10 mass % or more and 80 mass %or less. When the monomer concentration is lower than the above ranges,the reaction rate during polymerization tends to decrease. When themonomer concentration is higher than the above ranges, thepolymerization solution tends to be highly viscous.

The organic solvent or water can be removed from the resultingfluororesin precursor solution or dispersion by a method such asreprecipitation, filtration, or vacuum thermal distillation. Further,the resulting fluororesin precursor may be purified by, for example, amethod such as washing with a solvent that does not dissolve thefluororesin during filtration.

[Second Step]

In the second step, the formula (3-2b) between the repeating unitrepresented by the formula (3-1) and the repeating unit represented bythe formula (3-2b) is subjected to addition reaction with an acrylicacid derivative represented by the formula (3-2c) to produce afluororesin containing repeating units represented by the formulas (3-1)and (3-2).

The acrylic acid derivative represented by the formula (3-2c) may be acommercially available product or can be prepared by a known method or amethod based thereon. Use of a commercially available product ispreferred in terms of easy availability.

In the formula (3-2c), R³⁻⁶, Y³⁻², A³⁻², and n are the same as R³⁻⁶,Y³⁻², A³⁻², and n in the formula (3-2), respectively. Examples ofspecific substituents may include those of R³⁻⁶, Y³⁻², and A³⁻²described in “3-1-2. Repeating unit represented by formula (3-2)”.

Z³ represents an isocyanate group (—N═C═O), an acid halide (—C(═O)—X,wherein X is a halogen atom or an imidazolyl group), an acid anhydride,a halogen atom, a hydroxy group, a hydroxy group protected by aprotective group, an amino group (—NH₂), or an oxirane group.

Examples of the acid halide (—C(═O)—X, wherein X is a halogen atom or animidazolyl group) in Z³ include acid fluorides such as —C(═O)—F,—C(═O)—Cl, —C(═O)—Br, and —C(═O)—I, and groups in which —C(═O)— islinked to a 2-imidazolyl group.

Examples of the acid anhydride in Z³ include —C(═O)—O—C(═O)—CH₃,—C(═O)—O—C(═O)—C(CH₃)₃, and —C(═O)—O—C(═O)—CF₃.

Examples of the hydroxy group protected by a protective group in Z³include a hydroxy group protected by a protective group such as amethanesulfonyl group, a trifluoromethanesulfonyl group, or ap-toluenesulfonyl group.

Examples of the oxirane group in Z³ include an ethylene oxide group, a1,2-propylene oxide group, and a 1,3-propylene oxide group.

Of these, Z³ is particularly preferably an isocyanate group, —C(═O)—Cl,or an ethylene oxide group.

Examples of preferred acrylic acid derivatives represented by theformula (3-2c) include the following structures.

The form of the addition reaction varies depending on the type of Z³ inthe formula (3-2c), but in any form, a common addition reaction methodcan be used. Here, two forms are exemplified.

Form (3-1): When E³⁻² in the formula (3-2b) is a hydroxy group and Z³ inthe formula (3-2c) is an isocyanate group, W in the resulting formula(3-2) can form a bond “—O—C(═O)—NH—”.

Form (3-2): When E³⁻² in the formula (3-2b) is a hydroxy group and Z³ inthe formula (3-2c) is an ethylene oxide group, W³ in the resultingformula (3-2) can form a bond “—O—”.

Even when the fluororesin precursor containing the repeating unitsrepresented by the formulas (3-1) and (3-2b) further contains arepeating unit having a nucleophilic substituent such as a carboxy group(e.g., a repeating unit in which E³⁻¹ in the formula (3-3) is a carboxygroup, or a repeating unit in which B³ in the formula (3-4) is a hydroxygroup or a carboxy group), E³⁻² in the formula (3-2b) selectively reactswith the acrylic acid derivative represented by the formula (3-2c). Thisis because Z³ in the formula (3-2c) is reactive with E³⁻² in the formula(3-2b). The reactivity varies depending on the type of A³⁻¹ and E³⁻² inthe formula (3-2b), but when E³⁻² in the formula (3-2b) is a primaryalcohol, the reactivity between the formula (3-2b) and the formula(3-2c) is significant.

The method of the second step is described below. In any of the aboveforms, usually, the following method can be used.

The amount of the acrylic acid derivative represented by the formula(3-2c) to act on the fluororesin precursor containing the repeatingunits represented by the formulas (3-1) and (3-2b) is not limited, butis usually 0.01 to 5 mol, preferably 0.05 to 3 mol, more preferably 0.05to 1 mol, per mole of the fluororesin precursor containing the repeatingunits represented by the formulas (3-1) and (3-2b). The amount of theacrylic acid derivative is particularly preferably 0.2 to 1 mol.

Usually, the reaction is performed using an aprotic solvent such asdichloroethane, toluene, ethylbenzene, monochlorobenzene,tetrahydrofuran, acetonitrile, propylene glycol monomethyl monoacetate(PGMEA), or N,N-dimethylformamide. These solvents may be used alone orin combination of two or more thereof.

The reaction temperature is not limited, and is usually in the range of−20° C. to +100° C., preferably 0° C. to +80° C., more preferably +10°C. to +40° C. Preferably, the reaction is performed with stirring.

The reaction time depends on the reaction temperature, but is usuallyseveral minutes to 100 hours, preferably 30 minutes to 50 hours, morepreferably 1 to 20 hours. Preferably, a point at which the acrylic acidderivative represented by the formula (3-2c) is consumed is determined,by an analytical instrument such as a nuclear magnetic resonance (NMR)device, as the endpoint of the reaction.

In this reaction, a base may be used as a catalyst. Examples ofpreferred bases include organic bases such as trimethylamine,triethylamine, tripropylamine, tributylamine, and diisopropylethylamine;and inorganic bases such as sodium hydroxide, potassium hydroxide, andlithium hydroxide. The amount of the base catalyst used is not limited,but is 0.01 to 5 mol, preferably 0.02 to 3 mol, more preferably 0.05 to1 mol, per mole of the fluororesin precursor containing the repeatingunits represented by the formulas (3-1) and (3-2b).

After completion of the reaction, usual techniques such asreprecipitation, filtration, extraction, crystallization, andrecrystallization are performed, whereby a fluororesin containing arepeating unit represented by the formula (3-1) and a repeating unitrepresented by the formula (3-2) can be obtained. Further, the resultingfluororesin may be purified by, for example, a method such as washingwith a solvent that does not dissolve the fluororesin during filtration.

3-2. Photosensitive Resin Composition

The photosensitive resin composition according to the third embodimentof the present disclosure at least contains the fluororesin, a solvent,and a photopolymerization initiator.

The photosensitive resin composition according to the third embodimentof the present disclosure is particularly suitable as a negative resincomposition for obtaining a fluororesin film or banks for organic EL(described later).

In the photosensitive resin composition according to the thirdembodiment of the present disclosure, any solvent that can dissolve thefluororesin may be used, and examples thereof include ketones, alcohols,polyhydric alcohols and their derivatives, ethers, esters, aromaticsolvents, and fluorine solvents. These may be used alone or incombination of two or more thereof.

Specific examples of the ketones include acetone, methyl ethyl ketone,cyclopentanone, cyclohexanone, methyl isoamyl ketone, 2-heptanonecyclopentanone, methyl isobutyl ketone, methyl isopentyl ketone, and2-heptanone.

Specific examples of the alcohols include isopropanol, butanol,isobutanol, n-pentanol, isopentanol, tert-pentanol, 4-methyl-2-pentanol,3-methyl-3-pentanol, 2,3-dimethyl-2-pentanol, n-hexanol, n-heptanol,2-heptanol, n-octanol, n-decanol, s-amyl alcohol, t-amyl alcohol,isoamyl alcohol, 2-ethyl-1-butanol, lauryl alcohol, hexyl decanol, andoleyl alcohol.

Specific examples of the polyhydric alcohols and their derivativesinclude ethylene glycol, ethylene glycol monoacetate, ethylene glycoldimethyl ether, diethylene glycol, diethylene glycol dimethyl ether,diethylene glycol monoacetate, propylene glycol, propylene glycolmonoacetate, propylene glycol monomethyl ether (PGME), propylene glycolmonoethyl ether, propylene glycol monopropyl ether, propylene glycolmonobutyl ether, propylene glycol monomethyl ether acetate (PGMEA), andmonomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether,and monophenyl ether of dipropylene glycol or dipropylene glycolmonoacetate.

Specific examples of the ethers include diethyl ether, diisopropylether, tetrahydrofuran, dioxane, and anisole.

Specific examples of the esters include methyl lactate, ethyl lactate(EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate,ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate, andγ-butyrolactone.

Examples of the aromatic solvents include xylene and toluene.

Examples of the fluorine solvents include chlorofluorocarbons,hydrochlorofluorocarbons, perfluoro compounds, and hexafluoroisopropylalcohol.

Other solvents such as terpene-based petroleum naphtha solvents andparaffinic solvents, which are high-boiling-point weak solvents, canalso be used to improve coating properties.

Of these, preferably, the solvent is at least one selected from thegroup consisting of methyl ethyl ketone, cyclohexanone, methyl isoamylketone, 2-heptanone, ethylene glycol, ethylene glycol dimethyl ether,ethylene glycol monoacetate, diethylene glycol, diethylene glycolmonoacetate, diethylene glycol dimethyl ether, propylene glycol,propylene glycol monoacetate, propylene glycol monomethyl ether (PGME),propylene glycol monomethyl ether acetate (PGMEA), dipropylene glycol,dipropylene glycol monoacetate monomethyl ether, dipropylene glycolmonoacetate monoethyl ether, dipropylene glycol monoacetate monopropylether, dipropylene glycol monoacetate monobutyl ether, dipropyleneglycol monoacetate monophenyl ether, 1,4-dioxane, methyl lactate, ethyllactate, methyl acetate, ethyl acetate, butyl acetate, methylmethoxypropionate, ethyl ethoxypropionate, γ-butyrolactone, andhexafluoroisopropyl alcohol. More preferred are methyl ethyl ketone,propylene glycol monomethyl ether acetate (PGMEA), propylene glycolmonomethyl ether (PGME), cyclohexanone, ethyl lactate, butyl acetate,and γ-butyrolactone.

The amount of the solvent in the photosensitive resin compositionaccording to the third embodiment of the present disclosure is usually50 mass % or more and 2000 mass % or less, preferably 100 mass % or moreand 1000 mass % or less, relative to the concentration (100 mass %) ofthe fluororesin (when the photosensitive resin composition contains thelater-described alkali-soluble resin, the concentration is the sumincluding the alkali-soluble resin). The thickness of the resultingresin film can be adjusted by adjusting the amount of the solvent. Whenthe amount is in the above ranges, the resulting resin film has athickness particularly suitable to obtain banks for organic EL.

In the photosensitive resin composition according to the thirdembodiment of the present disclosure, any photopolymerization initiatorcan be used as long as it polymerizes the monomers having apolymerizable double bond exemplified in “3-1-7. Method of producingfluororesin” by electromagnetic waves or electron beams, and any knownphotopolymerization initiator can be used.

The photopolymerization initiator can be a photo-radical initiator or aphotoacid initiator. These may be used alone or may be used incombination with a photo-radical initiator and a photoacid initiator.Two or more photo-radical initiators or photoacid initiators may bemixed. Use of the photopolymerization initiator in combination withadditives enables living polymerization in some cases. Known additivescan be used.

Specifically, the photo-radical initiators can be classified into thefollowing types, for example: the intramolecular cleavage type thatcleaves the intermolecular bond by absorption of electromagnetic wavesor electron beams to generate radicals; and the hydrogen extraction typethat, when used in combination with a hydrogen donor such as a tertiaryamine or ether, generates radicals. Either type can be used. Aphoto-radical initiator of a type different from those described abovecan also be used.

Specific examples of the photo-radical initiators includebenzophenone-based, acetophenone-based, diketone-based, acylphosphineoxide-based, quinone-based, and acyloin-based photo-radical initiators.

Specific examples of the benzophenone-based photo-radical initiatorsinclude benzophenone, 4-hydroxybenzophenone, 2-benzoylbenzoic acid,4-benzoylbenzoic acid, 4,4′-bis(dimethylamino)benzophenone, and4,4′-bis(diethylamino)benzophenone. Preferred of these are2-benzoylbenzoic acid, 4-benzoylbenzoic acid, and4,4′-bis(diethylamino)benzophenone.

Specific examples of the acetophenone-based photo-radical initiatorsinclude acetophenone, 2-(4-toluenesulfonyloxy)-2-phenylacetophenone,p-dimethylaminoacetophenone, 2,2′-dimethoxy-2-phenylacetophenone,p-methoxyacetophenone,2-methyl-[4-(methylthio)phenyl]-2-morphorino-1-propanone, and2-benzyl-2-dimethylamino-1-(4-morphorinophenyl)-butan-1-one. Preferredof these are p-dimethylaminoacetophenone and p-methoxyacetophenone.

Specific examples of the diketone-based photo-radical initiators include4,4′-dimethoxybenzyl, methyl benzoylformate, and9,10-phenanthrenequinone. Preferred of these are 4,4′-dimethoxybenzyland methyl benzoylformate.

Specific examples of the acylphosphine oxide-based photo-radicalinitiators include bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide.

Specific examples of the quinone-based photo-radical initiators includeanthraquinone, 2-ethylanthraquinone, camphorquinone, and1,4-naphthoquinone. Preferred of these are camphorquinone and1,4-naphthoquinone.

Specific examples of the acyloin-based photo-radical initiators includebenzoin, benzoin methyl ether, benzoin ethyl ether, and benzoinisopropyl ether. Preferred of these are benzoin and benzoin methylether.

Preferred are benzophenone-based, acetophenone-based, and diketone-basedphoto-radical initiators. More preferred are benzophenone-basedphoto-radical initiators.

Examples of preferred commercially available photo-radical initiatorsinclude Irgacure 127, Irgacure 184, Irgacure 369, Irgacure 651, Irgacure819, Irgacure 907, Irgacure 2959, Irgacure OXE-01, Darocur 1173, andLucirin TPO (trade names) available from BASF. More preferred of theseare Irgacure 651 and Irgacure 369.

Specifically, the photoacid initiator is an onium salt of a pair ofcation and anion, the cation being at least one selected from the groupconsisting of aromatic sulfonic acid, aromatic iodonium, aromaticdiazonium, aromatic ammonium, thianthrenium, thioxanthonium, and(2,4-cyclopentadien-1-yl) (1-methylethylbenzene)-iron, the anion beingat least one selected from the group consisting of tetrafluoroborate,hexafluorophosphate, hexafluoroantimonate, and pentafluorophenyl borate.Particularly preferred of these arebis[4-(diphenylsulfonio)phenyl]sulfide bishexafluorophosphate,bis[4-(diphenylsulfonio)phenyl]sulfidetetrakis(pentafluorophenyl)borate, and diphenyliodoniumhexafluorophosphate.

Examples of commercially available photoacid generators includeCPI-100P, CPI-110P, CPI-101A, CPI-200K, and CPI-210S (trade names)available from San-Apro Ltd.; CYRACURE Photoinitiator UVI-6990, CYRACUREPhotoinitiator UVI-6992, and CYRACURE Photoinitiator UVI-6976 (tradenames) available from Dow Chemical Japan Limited; ADECA OPTOMER SP-150,ADECA OPTOMER SP-152, ADECA OPTOMER SP-170, ADECA OPTOMER SP-172, andADECA OPTOMER SP-300 (trade names) available from ADEKA; CI-5102 andCI-2855 (trade names) available from Nippon Soda Co., Ltd.; SAN AIDSI-60L, SAN AID SI-80L, SAN AID SI-100L, SAN AID SI-110L, SAN AIDSI-180L, SAN AID SI-110, and SAN AID SI-180 (trade names) available fromSanshin Chemical Industry Co. Ltd; Esacure 1064 and Esacure 1187 (tradenames) available from Lamberti; and Irgacure 250 (trade name) availablefrom Ciba Specialty Chemicals.

The amount of the photopolymerization initiator in the photosensitiveresin composition according to the third embodiment of the presentdisclosure is 0.1 mass % or more and 30 mass % or less, preferably 1mass % or more and 20 mass % or less, relative to 100 mass % of thefluororesin (when the photosensitive resin composition contains thelater-described alkali-soluble resin, the concentration is the sumincluding the alkali-soluble resin). When the amount of thephotopolymerization initiator is less than 0.1 mass %, the crosslinkingeffect tends to be insufficient. When the amount thereof is more than 30mass %, the resolution and sensitivity tend to be low.

Preferably, the photosensitive resin composition according to the thirdembodiment of the present disclosure essentially contains thefluororesin according to the third embodiment of the present disclosure,a solvent, and a photopolymerization initiator, and further contains acrosslinking agent (a) and an alkali-soluble resin (b). Thephotosensitive resin composition may further contain, for example, anaphthoquinonediazide group-containing compound (c), a basic compound(d), and other additives (e), if necessary.

(a) Crosslinking Agent

The crosslinking agent reacts with a repeating unit represented by theformula (3-2), whereby the resin can have a crosslinked structure. Thiscan improve the mechanical strength of the resulting film.

A known crosslinking agent can be used. Specific examples thereofinclude compounds obtained by reacting an amino group-containingcompound such as melamine, acetoguanamine, benzoguanamine, urea,ethylene urea, propylene urea, or glycoluril with formaldehyde orformaldehyde and a lower alcohol, and substituting a hydrogen atom ofthe amino group by a hydroxymethyl group or a lower alkoxymethyl group;polyfunctional epoxy compounds; polyfunctional oxetane compounds;polyfunctional isocyanate compounds; and polyfunctional acrylatecompounds. Here, those that use melamine are referred to asmelamine-based crosslinking agents, those that use urea are referred toas urea-based crosslinking agents, those that use alkylene urea suchethylene urea or propylene urea are referred to as alkylene urea-basedcrosslinking agents, and those that use glycoluril are referred to asglycoluril-based crosslinking agents. These crosslinking agents may beused alone or in combination of two or more thereof.

Preferably, the crosslinking agent is at least one selected from thesecrosslinking agents. Particularly preferred are glycoluril-basedcrosslinking agents and polyfunctional acrylate compounds.

Examples of the melamine-based crosslinking agents includehexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethylmelamine, and hexabutoxybutyl melamine. Preferred of these ishexamethoxymethyl melamine.

Examples of the urea-based crosslinking agents includebismethoxymethylurea, bisethoxymethylurea, bispropoxymethylurea, andbisbutoxymethylurea. Preferred of these is bismethoxymethylurea.

Examples of the alkylene urea-based crosslinking agents include ethyleneurea-based crosslinking agents such as mono- and/or di-hydroxymethylatedethylene urea, mono- and/or di-methoxymethylated ethylene urea, mono-and/or di-ethoxymethylated ethylene urea, mono- and/ordi-propoxymethylated ethylene urea, and mono- and/or di-butoxymethylatedethylene urea; propylene urea-based crosslinking agents such as mono-and/or di-hydroxymethylated propylene urea, mono- and/ordi-methoxymethylated propylene urea, mono- and/or di-ethoxymethylatedpropylene urea, mono- and/or di-propoxymethylated propylene urea, andmono- and/or di-butoxymethylated propylene urea;1,3-di(methoxymethyl)-4,5-dihydroxy-2-imidazolidinone; and1,3-di(methoxymethyl)-4,5-dimethoxy-2-imidazolidinone.

Examples of the glycoluril-based crosslinking agents include mono-, di-,tri-, and/or tetra-hydroxymethylated glycoluril; mono-, di-, tri-,and/or tetra-methoxymethylated glycoluril; mono-, di-, tri-, and/ortetra-ethoxymethylated glycoluril; mono-, di-, tri-, and/ortetra-propoxymethylated glycoluril; and mono-, di-, tri-, and/ortetra-butoxymethylated glycoluril.

Examples of the polyfunctional acrylate compounds include polyfunctionalacrylates (e.g., A-TMM-3, A-TMM-3L, A-TMM-3LM-N, A-TMPT, and AD-TMP(trade names) available from Shin-Nakamura Chemical Co., Ltd.);polyethylene glycol diacrylates (e.g., A-200, A-400, and A-600 (tradenames) available from Shin-Nakamura Chemical Co., Ltd.); urethaneacrylates (e.g., UA-122P, UA-4HA, UA-6HA, UA-6LPA, UA-11003H, UA-53H,UA-4200, UA-200PA, UA-33H, UA-7100, and UA-7200 (trade names) availablefrom Shin-Nakamura Chemical Co., Ltd.); and pentaerythritoltetraacrylate.

The following are examples of preferred polyfunctional acrylatecompounds.

The amount of the crosslinking agent in the photosensitive resincomposition according to the third embodiment of the present disclosureis 10 mass % or more and 300 mass % or less, preferably 50 mass % ormore and 200 mass % or less, relative to 100 mass % of the fluororesin(when the photosensitive resin composition contains the later-describedalkali-soluble resin, the concentration is the sum including thealkali-soluble resin). When the amount of the crosslinking agent is lessthan 10 mass %, the crosslinking effect tends to be insufficient. Whenthe amount thereof is more than 300 mass %, the resolution andsensitivity tend to be low.

(b) Alkali-Soluble Resin

The alkali-soluble resin has an effect of improving the shape of banksobtainable from the photosensitive resin composition according to thethird embodiment of the present disclosure, thus providing one preferredembodiment.

Examples of the alkali-soluble resin include alkali-soluble novolacresins.

Alkali-soluble novolac resins can be obtained by condensation of phenolwith aldehyde in the presence of an acid catalyst.

Specific examples of the phenol include phenol, o-cresol, m-cresol,p-cresol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol,3,4-dimethylphenol, 3,5-dimethylphenol, 2,3,5-trimethylphenol,3,4,5-trimethylphenol, resorcinol, 2-methylresorcinol,4-ethylresorcinol, hydroquinone, methylhydroquinone, catechol,4-methyl-catechol, pyrogallol, phloroglucinol, thymol, and isothymol.These phenols may be used alone or in combination of two or morethereof.

Specific examples of the aldehyde include formaldehyde, trioxane,paraformaldehyde, benzaldehyde, acetaldehyde, propylaldehyde,phenylacetaldehyde, α-phenylpropylaldehyde, β-phenylpropylaldehyde,o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde,o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde,nitrobenzaldehyde, furfural, glyoxal, glutaraldehyde,terephthalaldehyde, and isophthalaldehyde.

Specific examples of the acid catalyst include hydrochloric acid, nitricacid, sulfuric acid, phosphoric acid, phosphorous acid, formic acid,oxalic acid, acetic acid, methanesulfonic acid, diethyl sulfate, andp-toluenesulfonic acid. These acid catalysts may be used alone or incombination of two or more thereof.

Other examples of the alkali-soluble resin include acid-modified epoxyacrylic resins. Examples of commercially available acid-modified epoxyacrylic resins include CCR-1218H, CCR-1159H, CCR-1222H, CCR-1291H,CCR-1235, PCR-1050, TCR-1335H, UXE-3024, ZAR-1035, ZAR-2001H, ZFR-1185,and ZCR-1569H (trade names) available from Nippon Kayaku Co., Ltd.

The weight average molecular weight of the alkali-soluble resin ispreferably 1000 to 50000 in terms of developability and resolution ofthe photosensitive resin composition.

The amount of the alkali-soluble resin in the photosensitive resincomposition according to the third embodiment of the present disclosureis 500 mass % or more and 10000 mass % or less, preferably 1000 mass %or more and 7000 mass % or less, relative to 100 mass % of thefluororesin. When the amount of the alkali-soluble resin is more than10000 mass %, the fluororesin according to the third embodiment of thepresent disclosure tends to have insufficient ink repellency afterUV-ozone treatment or oxygen plasma treatment.

(c) Naphthoquinonediazide Group-Containing Compound

Any naphthoquinonediazide group-containing compound can be used, and onecommonly used as a photosensitive component of a resist composition fori-rays can be used. The naphthoquinonediazide group-containing compoundhas an effect of improving the shape of banks obtainable from thephotosensitive resin composition according to the third embodiment ofthe present disclosure, thus providing one preferred embodiment.

Specific examples of the naphthoquinonediazide group-containingcompounds include a naphthoquinone-1,2-diazide-4-sulfonate compound, anaphthoquinone-1,2-diazide-5-sulfonate compound, anaphthoquinone-1,2-diazide-6-sulfonate compound, anaphthoquinone-1,2-diazide sulfonate compound, anorthobenzoquinonediazide sulfonate compound, and anorthoanthraquinonediazide sulfonate compound. Preferred of these are anaphthoquinone-1,2-diazide-4-sulfonate compound, anaphthoquinone-1,2-diazide-5-sulfonate compound, and anaphthoquinone-1,2-diazide-6-sulfonate compound, because they haveexcellent solubility. These compounds may be used alone or incombination of two or more thereof.

The amount of the naphthoquinonediazide group-containing compound in thephotosensitive resin composition according to the third embodiment ofthe present disclosure is usually 10 mass % to 60 mass %, preferably 20mass % to 50 mass %, relative to 100 mass % of the fluororesin (when thephotosensitive resin composition contains the above-describedalkali-soluble resin, the concentration is the sum including thealkali-soluble resin). When the amount thereof is more than 60 wt %, thephotosensitive resin composition tends to lack sensitivity.

(d) Basic Compound

The basic compound functions to decrease the diffusion rate of an acidgenerated by the photoacid generator when the acid is diffused into thefilm according to the third embodiment of the present disclosure. Thepresence of the basic compound is likely to improve the shape of banksby adjusting the acid diffusion distance and increase the stability toobtain a bank shape with desired accuracy even when the banks formed areleft to stand for a long time before being exposed.

Examples of the basic compound include aliphatic amines, aromaticamines, heterocyclic amines, and aliphatic polycyclic amines. Preferredof these are aliphatic amines. Specific examples thereof includesecondary or tertiary aliphatic amines and alkyl alcohol amines. Thesebasic compounds may be used alone or in combination of two or morethereof.

Examples of the aliphatic amines include alkylamines and alkyl alcoholamines each in which at least one hydrogen atom of ammonia (NH₃) issubstituted by a C12 or lower alkyl group or a hydroxyalkyl group.Specific examples thereof include trimethylamine, triethylamine,tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine,tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine,tri-n-decanylamine, tri-n-dodecylamine, dimethylamine, diethylamine,di-n-propylamine, di-n-butylamine, di-n-pentylamine, di-n-hexylamine,di-n-heptylamine, di-n-octylamine, di-n-nonylamine, di-n-decanylamine,di-n-dodecylamine, dicyclohexylamine, methylamine, ethylamine,n-propylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine,n-octylamine, n-nonylamine, n-decanylamine, n-dodecylamine,diethanolamine, triethanolamine, diisopropanolamine,triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine.

Preferred of these are dialkylamine, trialkylamine, and alkyl alcoholamines. More preferred are alkyl alcohol amines. Particularly preferredof these alkyl alcohol amines are triethanolamine andtriisopropanolamine.

Examples of the aromatic amines and heterocyclic amines include anilineand aniline derivatives such as N-methylaniline, N-ethylaniline,N-propylaniline, N,N-dimethylaniline, 2-methylaniline, 3-methylaniline,4-methylaniline, ethylaniline, propylaniline, trimethylaniline,2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline,2,6-dinitroaniline, 3,5-dinitroaniline, and N,N-dimethyltoluidine;heterocyclic amines such as 1,5-diazabicyclo[4.3.0]non-5-en,1,8-diazabicyclo[5.4.0]undec-7-en, 1,4-diazabicyclo[2.2.2]octane,pyridine, bipyridine, 4-dimethylaminopyridine, hexamethylenetetramine,and 4,4-dimethylimidazoline; hindered amines such asbis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate; alcoholicnitrogen-containing compounds such as 2-hydroxypyridine, aminocresol,2,4-quinolinediol, 3-indolemethanol hydrate, monoethanolamine,diethanolamine, triethanolamine, N-ethyldiethanolamine,N,N-diethylethanolamine, triisopropanolamine, 2,2′-iminodiethanol,2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol,4-(2-hydroxyethyl)morpholine, 2-(2-hydroxyethyl)pyridine,1-(2-hydroxyethyl)piperazine, and1-[2-(2-hydroxyethoxy)ethyl]piperazine; and amines such as picoline,lutidine, pyrrole, piperidine, piperazine, indole, andhexamethylenetetramine.

The amount of the basic compound in the photosensitive resin compositionaccording to the third embodiment of the present disclosure is usually0.001 mass % to 2 mass %, preferably 0.01 mass % to 1 mass %, relativeto 100 mass % of the fluororesin (when the photosensitive resincomposition contains the above-described alkali-soluble resin, theconcentration is the sum including the alkali-soluble resin). When theamount of the basic compound is less than 0.001 mass %, the effectthereof as an additive tends to be insufficient. When the amount thereofis more than 2 mass %, the resolution and sensitivity tend to be low.

(e) Other Additives

The photosensitive resin composition according to the third embodimentof the present disclosure may contain other additives if necessary.Known additives may be suitably used as the other additives, andexamples thereof include various additives such as dissolutioninhibitors, plasticizers, stabilizers, colorants, surfactants,thickeners, leveling agents, defoamers, compatibility agents, adhesives,and antioxidants.

Preferably, the surfactant contains any one or more of fluorine-basedsurfactants and silicone-based surfactants (fluorine-based surfactants,silicone-based surfactants, and surfactants containing both fluorineatoms and silicon atoms).

3-3. Fluororesin Film

The fluororesin film according to the third embodiment of the presentdisclosure contains a repeating unit represented by the formula (3-1)and a repeating unit represented by the formula (3-2A). Specifically,the fluororesin film according to the third embodiment of the presentdisclosure is obtained by curing the photosensitive resin compositiondescribed above.

In the formula (3-1), R³⁻¹ represents a hydrogen atom, a fluorine atom,or a methyl group; R³⁻² represents a hydrogen atom or a C1-C6 linear,C3-C6 branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ eachindependently represent a fluorine atom, a C1-C10 linear, C3-C10branched, or C3-C10 cyclic alkyl group, or a C1-C10 linear, C3-C10branched, or C3-C10 cyclic fluoroalkyl group; and one or more of R³⁻¹,R³⁻³, and R³⁻⁴ are fluorine atoms or the fluoroalkyl groups.

In the formula (3-2A), R³⁻⁵ and R³⁻⁶ each independently represent ahydrogen atom or a methyl group; W³ is a divalent linking group andrepresents —O—, —O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—,or —C(═O)—NH—; A³⁻¹ and A³⁻² are divalent linking groups and eachindependently represent a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkylene group in which one or more hydrogen atoms in thealkylene group may be substituted by hydroxy groups or —O—C(═O)—CH₃;Y³⁻¹ and Y³⁻² are divalent linking groups and each independentlyrepresent —O— or —NH—; n represents an integer of 1 to 3; and rrepresents an integer of 0 or 1.

Examples of preferred structures of the repeating unit represented bythe formula (3-1) may include those described in “3-1-1. Repeating unitrepresented by formula (3-1)”.

The repeating unit represented by the formula (3-2A) is formed bycleavage of the polymerizable double bond of the repeating unitrepresented by the formula (3-2). No structural changes occur and theoriginal structure is maintained, except for the changes in thepolymerizable double bond during polymerization. Thus, in the repeatingunit represented by the formula (3-2A), R³⁻⁵, R³⁻⁶, W³, A³⁻¹, A³⁻²,Y³⁻¹, Y³⁻², n, and r are the same as R³⁻⁵, R³⁻⁶, W³, A³⁻¹, A³⁻², Y³⁻¹,Y³⁻², n, and r in the repeating unit represented by the formula (3-2),respectively. Examples of specific substituents may include thosedescribed in “3-1-2. Repeating unit represented by formula (3-2)”.Examples of preferred structures of the repeating unit represented bythe formula (3-2) may include the preferred structures described in“3-1-2. Repeating unit represented by formula (3-2)”, except that theyare formed by cleavage of the polymerizable double bond.

The fluororesin film according to the third embodiment of the presentdisclosure can be suitably used as a simple film not having a pattern.It can also be suitably used as a film having a pattern, i.e., banks(described later). Herein, the term “fluororesin film” refers to a filmnot having a pattern.

The fluororesin film according to the third embodiment of the presentdisclosure has excellent water repellency and oil repellency owing toits low surface free energy. For example, the fluororesin film can beused as a water- and oil-repellent agent for treating fabrics (basematerials) for clothes or the like, or a sealing agent for protectingsubstrates (base materials) for microfabricated semiconductors. Thefluororesin film can be used as a film to protect base materials invarious applications.

When forming a fluororesin film, it is particularly preferred that thephotosensitive resin composition essentially contains a fluororesin, asolvent, and a photopolymerization initiator and further contains acrosslinking agent. The photosensitive resin composition may containother additives if necessary. Examples of the solvent, thephotopolymerization initiator, the crosslinking agent, and the otheradditives may include those described above in “3-2. Photosensitiveresin composition”.

When pursuing properties other than the ink repellency of thefluororesin according to the third embodiment of the present disclosureafter UV-ozone treatment or oxygen plasma treatment, the fluororesin ismixed (blended) with other resins, whereby characteristics of otherresins can be incorporated.

The types of monomers of such “other resins” are not limited. Examplesthereof include styrene compounds, acrylic acid esters, and methacrylicacid esters. These may be homopolymers of one type or copolymers of twoor more types. Fluorine-free monomers are particularly preferred.

When forming a fluororesin film by mixing the fluororesin with the“other resins” as described above, the mass % of the fluororesinaccording to the third embodiment of the present disclosure relative to100 mass % of the fluororesin film is usually 50 mass % to 99 mass %,more preferably 60 mass % to 99 mass %, particularly preferably 70 mass% to 99 mass %. The rest are the “other resins” or “various additives”described above. When the amount of the fluororesin according to thethird embodiment of the present disclosure is less than 50 mass %, theink repellency tends to decrease after UV-ozone treatment or oxygenplasma treatment.

When forming a fluororesin film, the concentration of the fluororesinrelative to 100 mass % of the photosensitive resin composition ispreferably 1 mass % or more and 30 mass % or less, more preferably 2mass % or more and 20 mass % or less, to facilitate coating and filmformation.

A technique similar to conventionally known coating methods can beappropriately used as the method of forming a film using thephotosensitive resin composition according to the third embodiment ofthe present disclosure. A suitable method can be selected according to acoating target. For example, the fluororesin according to the thirdembodiment of the present disclosure can be suitably applied with anappropriate coating device such as a slit coater, die coater, gravurecoater, dip coater, or spin coater. A method such as immersion coating,spray coating, or roller coating can also be used.

After a fluororesin film is applied to a substrate, preferably, thesolvent contained in the photosensitive resin composition is dried andremoved from the fluororesin film.

The solvent can be removed by heating the substrate coated with thefluororesin film at 80° C. or higher and 300° C. or lower. Preferably,the heating is performed until a decrease in weight of the fluororesinfilm is no longer observed. The heating may be performed underatmospheric pressure, increased pressure, or reduced pressure. Further,the heating may be performed in air or inert atmospheres, or may beperformed under flow of a predetermined gas.

When the heating temperature is lower than 80° C., the solvent tends toremain. When the heating temperature is higher than 300° C., thefluororesin tends to decompose. More preferably, the heating temperatureis 100° C. or higher and 250° C. or lower, so that the solvent can beremoved without causing decomposition of the fluororesin.

The coating target may be a substrate for a microfabricatedsemiconductor or a fabric for clothes or the like.

Here, the fluororesin film to be formed on a base material may be formedon the entire or partial surface of the base material.

Preferably, the thickness of the resulting fluororesin film is 1 μm ormore and 500 μm or less. A fluororesin film thinner than 1 μm may havelow mechanical strength. A fluororesin film thicker than 500 μm tendsnot to be flat due to large recesses and protrusions on its surface.

3-4. Banks

The banks according to the third embodiment of the present disclosurecontain a repeating unit represented by the formula (3-1) and arepeating unit represented by the formula (3-2A). Specifically, thebanks according to the third embodiment of the present disclosure areobtained by curing the photosensitive resin composition described above.

When forming the banks according to the third embodiment of the presentdisclosure, it is particularly preferred that the photosensitive resincomposition essentially contains a fluororesin, a solvent, and aphotopolymerization initiator, and further contains a crosslinking agentand an alkali-soluble resin. The photosensitive resin composition mayfurther contain, for example, a naphthoquinonediazide group-containingcompound (c), a basic compound (d), and other additives (e), ifnecessary.

Examples of the compounds may include those described above in “3-2.Photosensitive resin composition”.

A resist pattern formation method of a conventional photoresisttechnique can be used as a method of forming the banks according to thethird embodiment of the present disclosure. The method of forming thebanks is described below.

The banks can be formed by a film forming step (4-1), an exposing step(4-2), a developing step (4-3), and a UV-ozone treatment or oxygenplasma treatment step (4-4). In the film forming step (4-1), thephotosensitive resin composition is applied to a substrate to form afilm. In the exposing step (4-2), the substrate is irradiated withelectromagnetic waves or electron beams through a photo mask to transfera photo mask pattern to the film. In the developing step (4-3), the filmis developed using a developer to form banks. In the UV-ozone treatmentor oxygen plasma treatment step (4-4), the residual organic matter orthe like in recesses between the banks is removed. Subsequently, aheating step (4-5) may be included if necessary.

Each step is described below with examples.

4-1. Film Forming Step

The film forming step is a step of forming a film on a substrate such asa silicon wafer by applying the photosensitive resin composition theretoby spin coating or the like and subsequently heating the silicon waferon a hot plate to remove a solvent. The solvent is removed by heatingusually at a temperature of 60° C. or higher and 200° C. or lower for 10seconds or more and 10 minutes or less, preferably at a temperature of80° C. or higher and 150° C. or lower for 30 seconds or more and 2minutes or less.

The substrate may be a silicon wafer, metal, glass, ITO substrate, orthe like. The substrate may include an organic or inorganic film formedthereon in advance. For example, the substrate may include ananti-reflective film and/or a multilayer resist underlayer, and such afilm and/or underlayer may have a pattern formed thereon. The substratemay be pre-washed. For example, the substrate may be washed withultrapure water, acetone, an alcohol (methanol, ethanol, or isopropylalcohol), or the like.

4-2. Exposing Step

The exposing step is a step of setting a desired photo mask in anexposure device, irradiating the film with electromagnetic waves orelectron beams through the photo mask, and then heating the film on ahot plate.

The wavelength of electromagnetic waves or electron beams used forexposure is preferably 100 to 600 nm, more preferably 300 to 500 nm, andthose containing i-rays (365 nm), h-rays (405 nm), and g-rays (436 nm)are particularly preferred. Light with a wavelength of 330 nm or lessmay be cut off if necessary.

Examples of light sources include KrF excimer laser light (wavelength:248 nm), ArF excimer laser light (wavelength: 193 nm), and F2 excimerlaser light (wavelength: 157 nm).

The amount of electromagnetic wave or electron beam exposure is 1 mJ/cm²or more and 200 mJ/cm² or less, preferably 10 mJ/cm² or more and 100mJ/cm² or less.

The heating after exposure is performed on a hot plate usually at atemperature of 60° C. or higher and 150° C. or lower for 10 seconds ormore and 5 minutes or less, preferably at a temperature of 80° C. orhigher and 130° C. or lower for 30 seconds or more and 3 minutes orless.

4-3. Developing Step

The developing step is a step of forming banks by dissolving, in adeveloper, the exposed or non-exposed portions of the film obtained inthe exposing step described above.

The developer may be, for example, an alkaline aqueous solution such asa tetramethylammonium hydroxide (TMAH) aqueous solution or atetrabutylammonium hydroxide (TBAH) aqueous solution, or an organicsolvent such as propylene glycol monomethyl ether acetate (PGMEA) orbutyl acetate.

The concentration of the tetramethylammonium hydroxide (TMAH) aqueoussolution is usually 0.1 mass % or more and 5 mass % or less, preferably2 mass % or more and 3 mass % or less.

Any known development method, such as dipping, paddling, or spraying,can be used.

The development time (contact time of the developer with the film) isusually 10 seconds or more and 3 minutes or less, preferably 30 secondsor more and 2 minutes or less.

After development, a step of washing the formed banks film withdeionized water or the like may be included if necessary. The washingmethod and washing time are as described above for the developmentmethod using a developer and development time.

The film after development is subjected to a heating step forcrosslinking and removing low-boiling fractions. The heating isperformed on a hot plate usually at a temperature of 60° C. or higherand 300° C. or lower for 10 seconds or more and 120 minutes or less,preferably at a temperature of 140° C. or higher and 250° C. or lowerfor 10 minutes or more and 90 minutes or less.

4-4. UV-Ozone Treatment or Oxygen Plasma Treatment Step

The UV-ozone treatment or oxygen plasma treatment step is a step ofirradiating the entire surface of the substrate having the banks formedthereon with UV-ozone or oxygen plasma to remove residual organic matteror the like in the recesses between the banks.

The UV-ozone treatment time is usually 10 seconds or more and 30 minutesor less, preferably 1 minute or more and 15 minutes or less.

The oxygen plasma treatment time is usually 10 seconds or more and 30minutes or less, preferably 1 minute or more and 15 minutes or less.

When the UV-ozone treatment or oxygen plasma treatment time is less than10 seconds, removal of residual organic matter tends to be incomplete.When the UV-ozone treatment or oxygen plasma treatment time is more than30 minutes, the thickness of the patterned film tends to decrease.

4-5. Heating Step

After the UV-ozone treatment or oxygen plasma treatment step, a heatingstep of heating the resulting banks may be performed if necessary. Thisstep can improve the liquid repellency of the upper surfaces of thebanks according to the third embodiment of the present disclosure.

The heating is performed on a hot plate usually at a temperature of 60°C. or higher and 300° C. or lower for 10 seconds or more and 30120minutes or less, preferably at a temperature of 140° C. or higher and250° C. or lower for 10 minutes or more and 1590 minutes or less.

Preferably, the heat treatment step is performed when the banksaccording to the third embodiment of the present disclosure contain arepeating unit represented by the formula (3-4) wherein B³ is a carboxygroup. Such banks are one embodiment especially capable of improving theink repellency by the heat treatment step.

3-5. Display Device

The display element according to the third embodiment of the presentdisclosure includes the banks.

Examples of the display element according to the third embodiment of thepresent disclosure include organic electroluminescence displays(hereinafter organic EL displays), micro-LED displays, and quantum dotdisplays.

Examples According to Third Embodiment

The third embodiment of the present disclosure is described in detailbelow with reference to examples but the present disclosure is notlimited to these examples.

1. Synthesis of Monomers [Synthesis Example 3-1] Synthesis of1,1-bistrifluoromethylbutadiene (BTFBE)

Synthesis of 1,1-bistrifluoromethylbutadiene (BTFBE) A 1000-ml glassflask equipped with a stirrer was charged with concentrated sulfuricacid (400 g) and heated to 100° C. Then,1,1,1-trifluoro-2-trifluoromethyl-4-penten-2-ol (300 g) was graduallydropped thereto over one hour. After dropping, the mixture was stirredat 100° C. for 60 minutes. No residual raw materials were detected by¹⁹F-NMR analysis of the reaction solution. Then, a fraction at 68° C. to70° C. was collected by atmospheric distillation from the reactionsolution, whereby 1,1-bistrifluoromethylbutadiene (hereinafter describedas BTFBE) was obtained (yield: 58%).

<Results of NMR Analysis>

¹H-NMR (solvent: deuterated chloroform; standard substance: TMS); δ(ppm) 5.95 (1H, dd) 6.05 (1H, dd), 6.85 (1H, m), 7.04 (1H, m) ¹⁹F-NMR(solvent: deuterated chloroform; standard substance: C₆D₆); δ (ppm)−65.3 (3F, m), −58.4 (3F, m)

[Synthesis Example 3-2] Synthesis of 4-hydroxystyrene (p-HO-St)

(The synthesis was performed with reference to Examples in JP 2016-98181A.)

A 1000-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with 4-acetoxystyrene (a product of TokyoChemical Industry Co., Ltd., hereinafter described as “p-AcO-St”) (100g) and methanol (300 g), which were mixed therein, and1,3,5-trihydroxybenzene (0.50 g; equivalent to 0.5 mass % of p-AcO-St)as a polymerization inhibitor was added to the mixture. Then, after thesolution was cooled to 0° C. in an ice bath, a sodium hydroxide aqueoussolution having a concentration of 12 mass % (corresponding to 1.0equivalent of p-AcO-St) was gradually dropped over 40 minutes, followedby stirring at 0° C. for 30 minutes. No residual raw materials weredetected by ¹H-NMR analysis of the reaction solution. Then, ahydrochloric acid aqueous solution having a concentration of 18 mass %(corresponding to 0.8 equivalents of p-AcO-St) was dropped over 30minutes, followed by stirring for 30 minutes. The pH of the solution wasmeasured to be 6. The resulting reaction solution was subjected toextraction with methyl-t-butylether (360 g) at room temperature (about20° C.), followed by washing twice with purified water (330 g). To theresulting organic layer was added 1,3,5-trihydroxybenzene in an amountequivalent to 1 mass % of 4-hydroxystyrene. Subsequently,4-hydroxystyrene was concentrated to 72 mass %, and added to n-octane (apoor solvent) cooled to 0° C. Then, the solution was placed in an icebath and stirred for one hour to precipitate crystals of4-hydroxystyrene. The crystals were filtered and further washed withn-octane. Then, the crystals were vacuum dried at 25° C. Thus, whitecrystals of 4-hydroxystyrene (hereinafter described as p-HO-St) wereobtained (yield: 66%).

[Synthesis Example 3-3] Synthesis of 1-glycerol Acrylate (GLMA)

A 1-L glass four-neck flask equipped with a reflux condenser, a droppingfunnel, a thermometer, an air inlet tube, and a stirrer was provided. A1 mass % sulfuric acid aqueous solution was added to the reaction vesseland stirred at 80° C. for two hours to wash the inside of the reactionvessel before reaction. After the sulfuric acid aqueous solution wasdischarged, the reaction vessel was charged with water (140 g (7.80mol)) and 98 mass % sulfuric acid (76.5 mg (0.78 mmol)), and heated inan oil bath with stirring. Subsequently, glycidyl acrylate (100 g (0.78mol)) premixed with hydroquinone (0.05 g) was dropped into the reactionvessel over five hours for reaction while air was introduced thereinto.The reaction was further continued for two hours with the temperaturemaintained at 80° C. to 85° C. After completion of the reaction, theacid value of the reaction solution was measured, and a 2% sodiumhydroxide aqueous solution was added in an amount equivalent to the acidvalue for neutralization. Further, hydroquinone (0.05 g) was added tothe reaction vessel, and the reaction vessel was heated to 70° C. in theoil bath while air was blown thereinto, followed by dehydration underpressure (about 4.0 to 13.3 kPa). Samples were taken at non-specifictime points during the reaction and dehydration. Examination for thepresence of a polymer in the sample solutions found no polymers. Aftercompletion of the dehydration, filtration was performed, whereby1-glycerol acrylate (hereinafter described as GLMA) with a purity of96.2% was obtained (103 g; yield: 90.3%). No polymers were found in theresulting GLMA.

2. Production of Fluororesin (First Step: Polymerization) [Measurementof Molar Ratio of Repeating Units] NMR

The molar ratio of the repeating units of the polymer was determinedfrom the measurements of ¹H-NMR, ¹⁹F-NMR, or ¹³C-NMR.

[Measurement of Polymer Molecular Weight] GPC

The weight average molecular weight Mw and the molecular weightdispersity (Mw/Mn: ratio of the weight average molecular weight Mw tothe number average molecular weight Mn) of the polymer were measured bya high-speed gel permeation chromatograph (hereinafter sometimesreferred to as GPC; model: HLC-8320 GPC available from TosohCorporation) with an ALPHA-M column and an ALPHA-2500 column (bothavailable from Tosoh Corporation) connected in series, usingtetrahydrofuran (THF) as a developing solvent. A refractive indexdifference detector was used.

2-1. Polymerization of Fluororesin Precursors [Synthesis of FluororesinPrecursor 3-1]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with BTFBE obtained in Synthesis Example 3-1(9.5 g (0.05 mol)), 2-hydroxyethyl vinyl ether (a product of TokyoChemical Industry Co., Ltd., hereinafter described as HEVE) (8.8 g (0.10mol)), 2-(perfluorohexyl)ethyl methacrylate (a product of Tokyo ChemicalIndustry Co., Ltd., hereinafter described as MA-C6F) (43.2 g (0.1 mol)),p-HO-St obtained in Synthesis Example 3-2 (9.0 g (0.75 mol)), and MEK(70 g). Then, 2,2′-azobis(2-methylbutyronitrile) (a product of TokyoChemical Industry Co., Ltd., hereinafter described as AIBN) (1.6 g(0.005 mol)) was added thereto, followed by degassing with stirring.Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 75° C. for reaction for sixhours. n-Heptane (350 g) was dropped into the reaction system, whereby atransparent viscous substance was precipitated. This viscous substancewas isolated by decantation. Vacuum drying was performed at 60° C. Thus,a fluororesin precursor 3-1 as a transparent viscous substance wasobtained (60 g; yield: 85%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-1 was as follows: BTFBE repeating unit:HEVE repeating unit:MA-C6Frepeating unit:p-HO-St repeating unit=16:26:33:25.

<Results of GPC Measurement>

Mw=4100, Mw/Mn=1.3 [Synthesis of Fluororesin Precursor 3-2]

The same procedure as in the synthesis of the fluororesin precursor 3-1was performed, except that p-HO-St was replaced by vinyl benzoic acid (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asVBA). Thus, a fluororesin precursor 3-2 containing the followingrepeating units was obtained (yield: 87%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-2 was as follows: BTFBE repeating unit:HEVE repeating unit:MA-C6Frepeating unit:VBA repeating unit=17:25:33:25.

<Results of GPC Measurement> Mw=3900, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-3]

The same procedure as in the synthesis of the fluororesin precursor 3-1was performed, except that HEVE was replaced by 2-hydroxyethylmethacrylate (a product of Tokyo Chemical Industry Co., Ltd.,hereinafter described as HEMA). Thus, a fluororesin precursor 3-3containing the following repeating units was obtained (yield: 90%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-3 was as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:HO-St repeating unit=20:28:30:22.

<Results of GPC Measurement> Mw=6500, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-4]

The same procedure as in the synthesis of the fluororesin precursor 3-2was performed, except that HEVE was replaced by 2-hydroxyethylmethacrylate (a product of Tokyo Chemical Industry Co., Ltd.,hereinafter described as HEMA). Thus, a fluororesin precursor 3-4containing the following repeating units was obtained (yield: 91%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-4 was as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:VBA repeating unit=19:27:31:23.

<Results of GPC Measurement> Mw=6800, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-5]

The same procedure as in the synthesis of the fluororesin precursor 3-3was performed, except that p-HO-St was replaced by1,1,1,3,3,3-hexafluoro-2-(4-vinylphenyl)propan-2-ol (a product ofCentral Glass Co., Ltd., hereinafter described as 4-HFA-St). Thus, afluororesin precursor 3-5 containing the following repeating units wasobtained (yield: 87%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-5 was as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:4-HFA-St repeating unit=16:26:33:25.

<Results of GPC Measurement> Mw=7100, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-6]

The same procedure as in the synthesis of the fluororesin precursor 3-3was performed, except that p-HO-St was replaced by p-acetoxystyrene (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asp-AcO-St). Thus, a fluororesin precursor 3-6 containing the followingrepeating units was obtained (yield: 88%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-6 was as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:p-AcO-St repeating unit=16:32:30:22.

<Results of GPC Measurement> Mw=7200, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-7]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with BTFBE obtained in Synthesis Example 3-1(9.5 g (0.05 mol)), HEMA (13.0 g (0.10 mol)), MA-C6F (43.2 g (0.1 mol)),methacrylic acid (8.6 g (0.10 mol)), a product of Tokyo ChemicalIndustry Co., Ltd., hereinafter described as MAA), styrene (7.8 g (0.75mol)), a product of Tokyo Chemical Industry Co., Ltd., hereinafterdescribed as St), and MEK (82 g). Then, AIBN (1.6 g (0.005 mol) wasadded thereto, followed by degassing with stirring. Subsequently, theflask was purged with nitrogen gas, and the temperature inside the flaskwas raised to 75° C. for reaction for six hours. n-Heptane (350 g) wasdropped into the reaction system, whereby a transparent viscoussubstance was precipitated. This viscous substance was isolated bydecantation. Vacuum drying was performed at 60° C. Thus, a fluororesinprecursor 3-7 as a transparent viscous substance was obtained (73 g;yield: 89%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-7 was as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:MAA repeating unit:St repeating unit=15:25:30:10:20.

<Results of GPC Measurement> Mw=7200, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-8]

The procedure as in the synthesis of the fluororesin precursor 3-7 wasperformed, except that methacrylic acid was replaced by acrylic acid (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asAA). Thus, a fluororesin precursor 3-8 containing the followingrepeating units was obtained (yield: 89%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-8 was as follows: BTFBE repeating unit:HEMA repeating unit:MA-C6Frepeating unit:AA repeating unit:St repeating unit=16:24:31:9:20.

<Results of GPC Measurement> Mw=6800, Mw/Mn=1.4 [Synthesis ofFluororesin Precursor 3-9]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with BTFBE obtained in Synthesis Example 3-1(9.5 g (0.05 mol)), GLMA obtained in Synthesis Example 3-3 (14.6 g (0.10mol)), 2-(perfluorohexyl)ethyl methacrylate (a product of Tokyo ChemicalIndustry Co., Ltd., hereinafter described as MA-C6F) (43.2 g (0.10mol)), p-HO-St obtained in Synthesis Example 3-2 (9.0 g (0.75 mol)), andMEK (70 g). Then, 2,2′-azobis(2-methylbutyronitrile) (a product of TokyoChemical Industry Co., Ltd., hereinafter descried as AIBN) (1.6 g (0.005mol)) was added thereto, followed by degassing with stirring.Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 75° C. for reaction for sixhours. n-Heptane (350 g) was dropped into the reaction system, whereby atransparent viscous substance was precipitated. This viscous substancewas isolated by decantation. Vacuum drying was performed at 60° C. Thus,a fluororesin precursor 3-9 as a transparent viscous substance wasobtained (61 g; yield: 80%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-9 was as follows: BTFBE repeating unit:GLMA repeating unit:MA-C6Frepeating unit:p-HO-St repeating unit=16:26:33:25.

<Results of GPC Measurement> Mw=5600, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-10]

The same procedure as in the synthesis of the fluororesin precursor 3-1was performed, except that p-HO-St was replaced by vinyl benzoic acid (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asVBA). Thus, a fluororesin precursor 3-10 containing the followingrepeating units was obtained (yield: 90%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-10 was as follows: BTFBE repeating unit:GLMA repeating unit:MA-C6Frepeating unit:VBA repeating unit=17:25:33:25.

<Results of GPC Measurement> Mw=5400, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-11]

The same procedure as in the synthesis of the fluororesin precursor 3-9was performed except that GLMA was replaced by 1-glycerol methacrylate(a product of NOF Corporation, hereinafter GLMM). Thus, a fluororesinprecursor 3-11 containing the following repeating units was obtained(yield: 92%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-11 was as follows: BTFBE repeating unit:GLMM repeating unit:MA-C6Frepeating unit:HO-St repeating unit=20:28:30:22.

<Results of GPC Measurement> Mw=7400, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-12]

The same procedure as in the synthesis of the fluororesin precursor 3-10was performed, except that GLMA was replaced by GLMM. Thus, afluororesin precursor 3-12 containing the following repeating units wasobtained (yield: 91%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-12 was as follows: BTFBE repeating unit:GLMM repeating unit:MA-C6Frepeating unit:VBA repeating unit=19:27:31:23.

<Results of GPC Measurement> Mw=7700, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-13]

The same procedure as in the synthesis of the fluororesin precursor 3-11was performed, except that p-HO-St was replaced by1,1,1,3,3,3-hexafluoro-2-(4-vinylphenyl)propan-2-ol (a product ofCentral Glass Co., Ltd., hereinafter described as 4-HFA-St). Thus, afluororesin precursor 3-13 containing the following repeating units wasobtained (yield: 85%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-13 was as follows: BTFBE repeating unit:GLMM repeating unit:MA-C6Frepeating unit:4-HFA-St repeating unit=16:26:33:25.

<Results of GPC Measurement> Mw=7900, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-14]

The same procedure as in the synthesis of the fluororesin precursor 3-11was performed, except that p-HO-St was replaced by p-acetoxystyrene (aproduct of Tokyo Chemical Industry Co., Ltd., hereinafter described asp-AcO-St). Thus, a fluororesin precursor 3-14 containing the followingrepeating units was obtained (yield: 89%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-14 was as follows: BTFBE repeating unit:GLMM repeating unit:MA-C6Frepeating unit:p-AcO-St repeating unit=16:32:30:22.

<Results of GPC Measurement> Mw=8200, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-15]

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with BTFBE obtained in Synthesis Example 3-1(9.5 g (0.05 mol)), GLMM (16.0 g (0.10 mol)), MA-C6F (43.2 g (0.1 mol)),methacrylic acid (8.6 g (0.10 mol)), a product of Tokyo ChemicalIndustry Co., Ltd., hereinafter described as MAA), styrene (7.8 g (0.75mol)), a product of Tokyo Chemical Industry Co., Ltd., hereinafterdescribed as St), and MEK (82 g). Then, AIBN (1.6 g (0.005 mol)) wasadded thereto, followed by degassing with stirring. Subsequently, theflask was purged with nitrogen gas, and the temperature inside the flaskwas raised to 75° C. for reaction for six hours. n-Heptane (350 g) wasdropped into the reaction system, whereby a transparent viscoussubstance was precipitated. This viscous substance was isolated bydecantation. Vacuum drying was performed at 60° C. Thus, a fluororesinprecursor 3-15 as a transparent viscous substance was obtained (75 g;yield: 88%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-15 was as follows: BTFBE repeating unit:GLMM repeating unit:MA-C6Frepeating unit:MAA repeating unit:St repeating unit=15:25:30:10:20.

<Results of GPC Measurement> Mw=8000, Mw/Mn=1.3 [Synthesis ofFluororesin Precursor 3-16]

The same procedure as in the synthesis of the fluororesin precursor 3-11was performed, except that p-HO-St was replaced by St. Thus, afluororesin precursor 3-16 containing the following repeating units wasobtained (yield: 89%).

<Results of NMR Measurement>

The ratio (in mol %) of the repeating units of the fluororesin precursor3-16 was as follows: BTFBE repeating unit:GLMM repeating unit:MA-C6Frepeating unit:St repeating unit=16:24:31:29.

<Results of GPC Measurement> Mw=7600, Mw/Mn=1.4 2-2. Synthesis ofComparative Fluororesin Precursor Comparative Polymerization Example 3-1

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with MA-C6F (43.2 g (0.1 mol)),hexafluoroisopropyl methacrylate (Central Glass Co., Ltd., hereinafterdescribed as HFIP-M) (23.6 g (0.1 mol)), MAA (17.32 g (0.2 mol)), andMEK (84 g). Then, AIBN (1.6 g (0.010 mol)) was added thereto, followedby degassing with stirring. Subsequently, the flask was purged withnitrogen gas, and the temperature inside the flask was raised to 80° C.,followed by reaction for six hours. The reaction solution after thereaction was dropped into n-heptane (500 g), whereby a white precipitatewas obtained. The precipitate was filtered and vacuum dried at 60° C., acomparative fluororesin precursor 3-1 as a white solid was obtained (55g; yield: 64%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-1 was as follows: MA-C6F repeating unit:HFIP-M repeatingunit:MAA repeating unit=26:20:54.

<Results of GPC Measurement> Mw=9700, Mw/Mn=1.5 ComparativePolymerization Example 3-2

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature with HEMA (13.01 g (0.1 mol)), MA-C6F (43.2 g (0.1 mol)),HFIP-M (23.6 g (0.1 mol)), MAA (8.66 g (0.1 mol)), and MEK (88 g). Then,AIBN (1.6 g (0.010 mol)) was added thereto, followed by degassing withstirring. Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 80° C., followed by reactionfor six hours. The reaction solution after the reaction was dropped inton-heptane (500 g), whereby a white precipitate was obtained. Theprecipitate was filtered and vacuum dried at 60° C., whereby acomparative fluororesin precursor 3-2 as a white solid was obtained (60g; yield: 68%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-2 was as follows: HEMA repeating unit:MA-C6F repeatingunit:HFIP-M repeating unit:MAA repeating unit=24:26:24:26.

<Results of GPC Measurement> Mw=10700, Mw/Mn=1.5 ComparativePolymerization Example 3-3

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature with p-HO-St (12.2 g (0.10 mol)), MA-C6F (43.2 g (0.1 mol)),HEVE (8.8 g (0.1 mol)), and MEK (63 g). Then, AIBN (1.6 g (0.010 mol))was added thereto, followed by degassing with stirring. Subsequently,the flask was purged with nitrogen gas, and the temperature inside theflask was raised to 80° C., followed by reaction for six hours. Thereaction solution after the reaction was dropped into n-heptane (500 g),whereby a white precipitate was obtained. The precipitate was filteredand vacuum dried at 60° C., whereby a comparative fluororesin precursor3-3 as a white solid was obtained (51 g; yield: 81%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-3 was as follows: HEVE repeating unit:MA-C6F repeatingunit:p-HO-St repeating unit=34:31:35.

<Results of GPC Measurement> Mw=14700, Mw/Mn=1.7 ComparativePolymerization Example 3-4

The same procedure as in the synthesis of the comparative fluororesinprecursor 3-3 was performed, except that p-HO-St was replaced by VBA.Thus, a comparative fluororesin precursor 3-4 containing the followingrepeating units was obtained (yield: 82%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-4 was as follows: HEVE repeating unit:MA-C6F repeatingunit:VBA repeating unit=35:31:34.

<Results of GPC Measurement> Mw=17300, Mw/Mn=1.7 ComparativePolymerization Example 3-5

The same procedure as in the synthesis of the comparative fluororesinprecursor 3-3 was performed, except that HEVE was replaced by HEMA.Thus, a comparative fluororesin precursor 3-5 containing the followingrepeating units was obtained (yield: 86%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-5 was as follows: HEMA repeating unit:MA-C6F repeatingunit:p-HO-St repeating unit=34:33:33.

<Results of GPC Measurement> Mw=19300, Mw/Mn=1.8 ComparativePolymerization Example 3-6

The same procedure as in the synthesis of the comparative fluororesinprecursor 3-4 was performed, except that HEVE was replaced by HEMA.Thus, a comparative fluororesin precursor 3-6 containing the followingrepeating units was obtained (yield: 83%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-6 was as follows: HEMA repeating unit:MA-C6F repeatingunit:VBA repeating unit=32:33:35.

<Results of GPC Measurement> Mw=17300, Mw/Mn=1.7 ComparativePolymerization Example 3-7

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature (about 20° C.) with MA-C6F (43.2 g (0.1 mol)),hexafluoroisopropyl methacrylate (Central Glass Co., Ltd., hereinafterdescribed as HFIP-M) (23.6 g (0.1 mol)), MAA (17.32 g (0.2 mol)), andMEK (84 g). Then, AIBN (1.6 g (0.010 mol)) was added thereto, followedby degassing with stirring. Subsequently, the flask was purged withnitrogen gas, and the temperature inside the flask was raised to 80° C.,followed by reaction for six hours. The reaction solution after thereaction was dropped into n-heptane (500 g), whereby a white precipitatewas obtained. The precipitate was filtered and vacuum dried at 60° C.,whereby a comparative fluororesin precursor 3-7 as a white solid wasobtained (55 g; yield: 64%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-7 was as follows: MA-C6F repeating unit:HFIP-M repeatingunit:MAA repeating unit=26:20:54.

<Results of GPC Measurement> Mw=9700, Mw/Mn=1.5 ComparativePolymerization Example 3-8

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature with GLMM (16.02 g (0.1 mol)), MA-C6F (43.2 g (0.1 mol)),HFIP-M (23.6 g (0.1 mol)), MAA (8.66 g (0.1 mol)), and MEK (88 g). Then,AIBN (1.6 g (0.010 mol)) was added thereto, followed by degassing withstirring. Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 80° C., followed by reactionfor six hours. The reaction solution after the reaction was dropped inton-heptane (500 g), whereby a white precipitate was obtained. Theprecipitate was filtered and vacuum dried at 60° C., whereby acomparative fluororesin precursor 3-8 as a white solid was obtained (65g; yield: 71%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-8 was as follows: GLMM repeating unit:MA-C6F repeatingunit:HFIP-M repeating unit:MAA repeating unit=24:26:24:26.

<Results of GPC Measurement> Mw=11500, Mw/Mn=1.5 ComparativePolymerization Example 3-9

A 300-ml glass flask equipped with a stirrer was charged at roomtemperature with GLMA (14.6 g (0.10 mol)), MA-C6F (43.2 g (0.1 mol)),p-HO-St (12.2 g (0.10 mol)), and MEK (63 g). Then, AIBN (1.6 g (0.010mol)) was added thereto, followed by degassing with stirring.Subsequently, the flask was purged with nitrogen gas, and thetemperature inside the flask was raised to 80° C., followed by reactionfor six hours. The reaction solution after the reaction was dropped inton-heptane (500 g), whereby a white precipitate was obtained. Theprecipitate was filtered and vacuum dried at 60° C., whereby acomparative fluororesin precursor 3-9 as a white solid was obtained (59g; yield: 84%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-9 was as follows: GLMA repeating unit:MA-C6F repeatingunit:p-HO-St repeating unit=34:31:35.

<Results of GPC Measurement> Mw=16700, Mw/Mn=1.7 ComparativePolymerization Example 3-10

The same procedure as in the synthesis of the comparative fluororesinprecursor 3-9 was performed, except that p-HO-St was replaced by VBA.Thus, a comparative fluororesin precursor 3-10 containing the followingrepeating units was obtained (yield: 86%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-10 was as follows: GLMA repeating unit:MA-C6F repeatingunit:VBA repeating unit=35:31:34.

<Results of GPC Measurement> Mw=19300, Mw/Mn=1.7 ComparativePolymerization Example 3-11

The same procedure as in the synthesis of the comparative fluororesinprecursor 3-9 was performed, except that GLMA was replaced by GLMM.Thus, a comparative fluororesin precursor 3-11 containing the followingrepeating units was obtained (yield: 86%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-11 was as follows: GLMM repeating unit:MA-C6F repeatingunit:p-HO-St repeating unit=33:34:33.

<Results of GPC Measurement> Mw=20400, Mw/Mn=1.8 ComparativePolymerization Example 3-12

The same procedure as in the synthesis of the comparative fluororesinprecursor 3-10 was performed, except that GLMA was replaced by GLMM.Thus, a comparative fluororesin precursor 3-12 containing the followingrepeating units was obtained (yield: 88%).

<Results of NMR Measurement>

The molar ratio of the repeating units of the comparative fluororesinprecursor 3-12 was as follows: GLMM repeating unit:MA-C6F repeatingunit:VBA repeating unit=32:33:35.

<Results of GPC Measurement> Mw=18300, Mw/Mn=1.7

Tables 3-1 and 3-2 show the repeating units of the resulting fluororesinprecursors 3-1 to 3-16 and comparative fluororesin precursors 3-1 to3-12, molar ratio of the repeating units, and weight average molecularweight (Mw), molecular weight distribution (Mw/Mn), and yield of each ofthe fluororesin precursors and comparative fluororesin precursors.

TABLE 3-1 Composition (repeating units) (mol %) Molecular weight Polymer3-1 3-2b 3-3 3-4 3-5 Mw Mw/Mn Yield (%) Fluororesin BTFBE HEVE MA-C6F —p-HO-St 4,100 1.3 85 precursor 3-1 16 26 33 25 Fluororesin BTFBE HEVEMA-C6F — VBA 3,900 1.3 87 precursor 3-2 17 25 33 25 Fluororesin BTFBEHEMA MA-C6F — p-HO-St 6,500 1.3 90 precursor 3-3 20 28 30 22 FluororesinBTFBE HEMA MA-C6F — VBA 6,800 1.3 91 precursor 3-4 19 27 31 23Fluororesin BTFBE HEMA MA-C6F — 4-HFA-St 7,100 1.3 87 precursor 3-5 1626 33 25 Fluororesin BTFBE HEMA MA-C6F — p-AcO-St 7,200 1.3 88 precursor3-6 16 32 30 22 Fluororesin BTFBE HEMA MA-C6F MAA St 7,200 1.3 89precursor 3-7 15 25 30 10 20 Fluororesin BTFBE HEMA MA-C6F AA St 6,8001.4 89 precursor 3-8 16 24 31 9 20 Fluororesin BTFBE GLMA MA-C6F —p-HO-St 5,600 1.3 80 precursor 3-9 16 26 33 25 Fluororesin BTFBE GLMAMA-C6F — VBA 5,400 1.3 90 precursor 3-10 17 25 33 25 Fluororesin BTFBEGLMM MA-C6F — p-HO-St 7,400 1.3 92 precursor 3-11 20 28 30 22Fluororesin BTFBE GLMM MA-C6F — VBA 7,700 1.3 91 precursor 3-12 19 27 3123 Fluororesin BTFBE GLMM MA-C6F — 4-HFA-St 7,900 1.3 85 precursor 3-1316 26 33 25 Fluororesin BTFBE GLMM MA-C6F — p-AcO-St 8,200 1.3 89precursor 3-14 16 32 30 22 Fluororesin BTFBE GLMM MA-C6F MAA St 8,0001.3 88 precursor 3-15 15 25 30 10 20 Fluororesin BTFBE GLMM MA-C6F St7,600 1.4 89 precursor 3-16 16 24 31 29

TABLE 3-2 Composition (repeating units) (mol %) Molecular weight Polymer3-1 3-2b 3-3 3-4 3-5 Mw Mw/IVh Yield (%) Comparative — — MA-C6F — MAA9,700 1.5 64 fluororesin 26 54 precursor 3-1 HFIP-M 20 Comparative —HEMA MA-C6F — MAA 10,700 1.5 68 fluororesin 24 26 26 precursor 3-2HFIP-M 24 Comparative — HEVE MA-C6F — p-HO-St 14,700 1.7 81 fluororesin34 31 35 precursor 3-3 Comparative — HEVE MA-C6F — VBA 17,300 1.7 82fluororesin 35 31 34 precursor 3-4 Comparative — HEMA MA-C6F — p-HO-St19,300 1.8 86 fluororesin 33 34 33 precursor 3-5 Comparative — HEMAMA-C6F — VBA 17,300 1.7 83 fluororesin 32 33 35 precursor 3-6Comparative — — MA-C6F — MAA 9,700 1.5 64 fluororesin 26 54 precursor3-7 HFIP-M 20 Comparative — GLMM MA-C6F — MAA 11,500 1.5 71 fluororesin24 26 26 precursor 3-8 HFIP-M 24 Comparative — GLMA MA-C6F — p-HO-St16,700 1.7 84 fluororesin 34 31 35 precursor 3-9 Comparative — GLMAMA-C6F — VBA 19,300 1.7 86 fluororesin 35 31 34 precursor 3-10Comparative — GLMM MA-C6F — p-HO-St 20,400 1.8 86 fluororesin 33 34 33precursor 3-11 Comparative — GLMM MA-C6F — VBA 18,300 1.7 88 fluororesin32 33 35 precursor 3-12

3. Production of Fluororesin (Second Step: Addition Reaction)

The fluororesin precursors 3-1 to 3-16 and comparative fluororesinprecursors 3-1 to 3-12 obtained in “2. Production of fluororesin (firststep: polymerization)” were each reacted with an acrylic acidderivative, whereby fluororesins were synthesized. The acrylic acidderivative was KarenzAOI, KarenzBEI (products of Showa Denko K.K.), orglycidyl acrylate (a product of Tokyo Chemical Industry Co., Ltd.). Thisreaction is an addition reaction of hydroxy groups of each fluororesinprecursor and the acrylic acid derivative.

Described below are fluororesin synthesis examples. The resultingfluororesins were named as follows. The first number represents thenumber of the fluororesin precursor. The subsequent alphabet letterrepresents the acrylic acid derivative used. KarenzAOI is represented by“A”, KarenzBEI is represented by “B”, and glycidyl acrylate isrepresented by “G”. The last number in the parenthesis indicates thenominal amount of acrylic acid derivative introduced relative to theresin precursor.

[Synthesis of Fluororesin 3-1-A (50)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 3-1 (10 g) (hydroxy equivalent: 0.0115 mol) andPGMEA (20 g). Then, KarenzAOI (0.81 g (0.0058 mol)) was added thereto,and a reaction was carried out at 45° C. for four hours. Aftercompletion of the reaction, the reaction solution was concentrated, andn-heptane (150 g) was then added to obtain a precipitate. Theprecipitate was filtered and vacuum dried at 40° C., whereby afluororesin 3-1-A (50) as a white solid was obtained (9.1 g; yield:84%).

<Results of NMR Measurement>

In the fluororesin 3-1-A (50), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 46:54. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-1 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—C(═O)—NH—”.

[Synthesis of Fluororesin 3-1-A (100)]

The same procedure as in the synthesis of the fluororesin 3-1-A (50) wasperformed, except that KarenzAOI was used in an amount of 1.62 g (0.0114mol). Thus, a fluororesin 3-1-A (100) containing the following repeatingunits was obtained (yield: 96%).

<Results of ¹³C-NMR Measurement>

In the fluororesin 3-1-A (100), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 96:4. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-1 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—C(═O)—NH—”.

[Synthesis of Fluororesin 3-1-B (50)]

The same procedure as in the synthesis of the fluororesin 3-1-A (50) wasperformed, except that KarenzAOI was replaced by KarenzBEI (1.38 g(0.0058 mol)). Thus, a fluororesin 3-1-B (50) containing the followingrepeating units was obtained (yield: 93%).

<Results of ¹³C-NMR Measurement>

In the fluororesin 3-1-B (50), the molar ratio of the amount ofKarenzBEI-derived acrylic groups introduced (reaction rate) to theamount of residual hydroxy groups (non-reaction rate) was 49:51. In thefluororesin 3-1-A (100), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 96:4. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-1 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—C(═O)—NH—”.

[Synthesis of Fluororesin 3-1-G (50)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 3-1 (10 g) (hydroxy equivalent: 0.0115 mol) andPGMEA (20 g). Then, glycidyl acrylate (1.4 g (0.0113 mol)) was addedthereto, and a reaction was carried out at 80° C. for 18 hours. Thecontent after the reaction was concentrated, and heptane (150 g) wasthen added to obtain a precipitate. The precipitate was filtered andvacuum dried at 40° C., whereby a fluororesin 3-1-G (50) as a whitesolid was obtained (10 g; yield: 88%).

<Results of ¹³C-NMR Measurement>

In the fluororesin 3-1-G (50), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 55:45. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-1 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—”.

[Synthesis of Fluororesins 3-2-A (50) to 3-8-G (50)]

Fluororesins 3-2-A (50) to 3-8-G (50) were produced as in thefluororesin 3-1-A (50), 3-1-A (100), or 3-1-G (50). Table 3-3 shows thefluororesin precursors used, acrylic acid derivative, crosslinking groupstructure formed (W³ in the formula (3-2)), amount of crosslinkinggroups introduced (reaction rate), amount of residual hydroxy groups(non-reaction rate), weight average molecular weight (Mw), and molecularweight distribution (Mw/Mn).

[Synthesis of Fluororesin 3-9-A (50)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 3-9 (10 g (hydroxy equivalent: 0.0230 mol)) andPGMEA (20 g). Then, KarenzAOI (1.62 g (0.0115 mol)) was added thereto,and a reaction was carried out at 45° C. for four hours. Aftercompletion of the reaction, the reaction solution was concentrated, andn-heptane (150 g) was then added to obtain a precipitate. Theprecipitate was filtered and vacuum dried at 40° C., whereby afluororesin 3-9-A (50) as a white solid was obtained (9.3 g; yield:80%).

<Results of NMR Measurement>

In the fluororesin 3-9-A (50), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 47:53. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-9 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—C(═O)—NH—”.

[Synthesis of Fluororesin 3-9-A (100)]

The same procedure as in the synthesis of the fluororesin 3-9-A (50) wasperformed, except that KarenzAOI was used in an amount of 3.24 g (0.0230mol). Thus, a fluororesin 3-9-A (100) containing the following repeatingunits was obtained (yield: 90%).

<Results of ¹³C-NMR Measurement>

In the fluororesin 3-9-A (100), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount of residual hydroxy groups (non-reaction rate) was 95:5. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-9 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—C(═O)—NH—”.

[Synthesis of Fluororesin 3-9-B (50)]

The same procedure as in the synthesis of the fluororesin 3-9-A (50) wasperformed, except that KarenzAOI was replaced by KarenzBEI (2.75 g(0.0115 mol)). Thus, a fluororesin 3-9-B (50) containing the followingrepeating units was obtained (yield: 92%).

<Results of ¹³C-NMR Measurement>

In the fluororesin 3-9-B (50), the molar ratio of the amount ofKarenzBEI-derived acrylic groups introduced (reaction rate) to theamount of residual hydroxy groups (non-reaction rate) was 49:51. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-9 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—C(═O)—NH—”.

[Synthesis of Fluororesin 3-9-G (50)]

A 300-ml glass flask equipped with a stirrer was charged with thefluororesin precursor 3-9 (10 g) (hydroxy equivalent: 0.0230 mol) andPGMEA (20 g). Then, glycidyl acrylate (1.5 g (0.0115 mol)) was addedthereto, and a reaction was carried out at 80° C. for 18 hours. Thecontent after the reaction was concentrated, and heptane (150 g) wasthen added to obtain a precipitate. The precipitate was filtered andvacuum dried at 40° C., whereby a fluororesin 3-9-G (50) as a whitesolid was obtained (10 g; yield: 87%).

<Results of ¹³C-NMR Measurement>

In the fluororesin 3-9-G (50), the molar ratio of the amount ofKarenzAOI-derived acrylic acid derivative introduced (reaction rate) tothe amount (non-reaction rate) of residual hydroxy groups was 53:47. Theratio of the repeating units (BTFBE repeating unit, MA-C6F repeatingunit, and p-HO-St repeating unit) that do not react with a crosslinkinggroup site was found to be unchanged from that in the fluororesinprecursor 3-9 used (i.e., same as before the introduction of thecrosslinking group). The newly formed bond (W³ in the formula (3-2)) was“—O—”.

[Synthesis of Fluororesins 3-10-A (50) to 3-16-G (50)]

Fluororesins 3-10-A (50) to 3-16-G (50) were produced as in thefluororesin 3-9-A (50), 3-9-A (100), or 3-9-G (50). Table 3-4 shows thefluororesin precursors used, acrylic acid derivative, crosslinking groupstructure formed (W³ in the formula (3-2)), amount of crosslinkinggroups introduced (reaction rate), amount of residual hydroxy groups(non-reaction rate), weight average molecular weight (Mw), and molecularweight distribution (Mw/Mn).

[Synthesis of Comparative Fluororesins 3-1-A (50) to 3-6-G (50)]

Comparative fluororesins 3-1-A (50) to 3-6-G (50) were produced as inthe fluororesin 3-1-A (50), 3-1-A (100), or 3-1-G (50). Table 3-5 showsthe comparative fluororesin precursors used, acrylic acid derivative,crosslinking group structure formed, amount of crosslinking groupsintroduced (reaction rate), amount of residual hydroxy groups(non-reaction rate), weight average molecular weight (Mw), and molecularweight distribution (Mw/Mn).

Comparative fluororesins 3-7-A (50) to 3-12-G (50) were produced as inthe fluororesin 3-9-A (50), 3-9-A (100), or 3-9-G (50). Table 3-5 showsthe comparative fluororesin precursors used, acrylic acid derivative,crosslinking group structure formed, amount of crosslinking groupsintroduced (reaction rate), amount of residual hydroxy groups(non-reaction rate), weight average molecular weight (Mw), and molecularweight distribution (Mw/Mn).

TABLE 3-3 Ratio of acrylic acid derivative Introduced introduced (mol %)Fluororesin crosslinking Amount of acrylic Fluororesin precursor groupsite Formed bond acid derivative Amount of residual Molecular weight No.No. (3-2c) (W³ in formula (3-2)) introduced hydroxy groups Mw Mw/Mn3-1-A (50) 3-1 A —O—C(═O)—NH— 46 54 5,600 1.4 3-1-A (100) 3-1 A—O—C(═O)—NH— 96 4 7,100 1.4 3-1-B (50) 3-1 B —O—C(═O)—NH— 49 51 6,1001.4 3-1-G (50) 3-1 G —O— 55 45 5,600 1.4 3-2-A (50) 3-2 A —O—C(═O)—NH—51 49 5,300 1.3 3-2-B (50) 3-2 B —O—C(═O)—NH— 47 53 5,700 1.3 3-2-G (50)3-2 G —O— 48 52 5,300 1.3 3-3-A (50) 3-3 A —O—C(═O)—NH— 52 48 8,000 1.33-3-B (40) 3-3 B —O—C(═O)—NH— 45 55 8,300 1.3 3-3-G (50) 3-3 G —O— 47 538,000 1.3 3-4-A (50) 3-4 A —O—C(═O)—NH— 51 49 8,300 1.3 3-4-B (40) 3-4 B—O—C(═O)—NH— 48 52 8,600 1.3 3-4-G (50) 3-4 G —O— 53 47 8,300 1.3 3-5-A(50) 3-5 A —O—C(═O)—NH— 54 46 8,600 1.3 3-5-B (45) 3-5 B —O—C(═O)—NH— 4753 9,100 1.3 3-5-G (50) 3-5 G —O— 48 52 8,600 1.3 3-6-A (50) 3-6 A—O—C(═O)—NH— 53 47 8,700 1.4 3-6-B (40) 3-6 B —O—C(═O)—NH— 40 60 8,9001.4 3-6-G (50) 3-6 G —O— 46 54 8,700 1.4 3-7-A (50) 3-5 A —O—C(═O)—NH—54 46 8,700 1.3 3-7-B (45) 3-5 B —O—C(═O)—NH— 44 56 9,200 1.3 3-7-G (50)3-5 G —O— 48 52 8,700 1.3 3-S-A (50) 3-6 A —O—C(═O)—NH— 53 47 8,300 1.43-8-B (40) 3-6 B —O—C(═O)—NH— 38 52 8,500 1.4 3-8-G (50) 3-6 G —O— 46 548,300 1.4

TABLE 3-4 Ratio of acrylic acid Introduced derivative introduced (mol %)crosslinking Amount of acrylic Fluororesin group site Formed bond acidderivative Amount of residual Molecular weight Fluororesin No. precursorNo. (3-2c) (W³ in formula (3-2)) introduced hydroxy groups Mw Mw/Mn3-9-A (50) 3-1 A —O—C(═O)—NH— 47 53 8,500 1.4 3-9-A (100) 3-1 A—O—C(═O)—NH— 95 5 11,600 1.5 3-9-B (50) 3-1 B —O—C(═O)—NH— 49 51 9,4001.4 3-9-G (50) 3-1 G —O— 53 47 8,400 1.4 3-10-A (50) 3-2 A —O—C(═O)—NH—50 50 8,200 1.3 3-10-B (50) 3-2 B —O—C(═O)—NH— 48 52 9,000 1.3 3-10-G(50) 3-2 G —O— 49 51 8,100 1.3 3-11-A (50) 3-3 A —O—C(═O)—NH— 51 4910,600 1.3 3-11-B (40) 3-3 B —O—C(═O)—NH— 43 57 11,600 1.3 3-11-G (50)3-3 G —O— 50 50 10,500 1.3 3-12-A (50) 3-4 A —O—C(═O)—NH— 52 48 10,8001.4 3-12-B (40) 3-4 B —O—C(═O)—NH— 46 54 11,700 1.4 3-12-G (50) 3-4 G—O— 54 46 10,600 1.4 3-13-A (50) 3-5 A —O—C(═O)—NH— 55 45 10,800 1.33-13-B (45) 3-5 B —O—C(═O)—NH— 46 54 11,600 1.3 3-13-G (50) 3-5 G —O— 4852 10,800 1.3 3-14-A (50) 3-6 A —O—C(═O)—NH— 53 47 11,900 1.4 3-14-B(40) 3-6 B —O—C(═O)—NH— 41 59 13,000 1.4 3-14-G (50) 3-6 G —O— 48 5211,800 1.4 3-15-A (50) 3-5 A —O—C(═O)—NH— 52 48 10,900 1.3 3-15-B (45)3-5 B —O—C(═O)—NH— 44 56 11,800 1.3 3-15-G (50) 3-5 G —O— 49 51 10,8001.3 3-16-A (50) 3-6 A —O—C(═O)—NH— 51 49 10,300 1.4 3-16-B (40) 3-6 B—O—C(═O)—NH— 49 51 11,100 1.4 3-16-G (50) 3-6 G —O— 46 54 10,300 1.4

TABLE 3-5 Ratio of acrylic acid Introduced derivative introduced (mol %)Comparative crosslinking Amount of acrylic Comparative fluororesin groupsite acid derivative Amount of residual Molecular weight fluororesin No.precursor No. (3-2c) Formed bond introduced hydroxy groups Mw Mw/MnComparative 3-1-A (50) Comparative 3-1 A —O—C(═O)—NH— 50 50 11,200 1.5Comparative 3-1-B (50) Comparative 3-1 B —O—C(═O)—NH— 53 47 11,700 1.5Comparative 3-1-G (50) Comparative 3-1 G —O— 52 48 11,200 1.5Comparative 3-2-A (50) Comparative 3-2 A —O—C(═O)—NH— 49 51 12,200 1.5Comparative 3-2-B (45) Comparative 3-2 B —O—C(═O)—NH— 44 56 12,700 1.5Comparative 3-2-G (50) Comparative 3-2 G —O— 52 48 12,200 1.5Comparative 3-3-A (50) Comparative 3-3 A —O—C(═O)—NH— 51 49 16,200 1.7Comparative 3-3-B (40) Comparative 3-3 B —O—C(═O)—NH— 41 59 16,700 1.7Comparative 3-3-G (50) Comparative 3-3 G —O— 48 52 16,200 1.7Comparative 3-4-A (50) Comparative 3-4 A —O—C(═O)—NH— 49 51 18,800 1.7Comparative 3-4-B (45) Comparative 3-4 B —O—C(═O)—NH— 51 49 18,800 1.7Comparative 3-4-G (50) Comparative 3-4 G —O— 50 50 19,300 1.7Comparative 3-5-A (50) Comparative 3-3 A —O—C(═O)—NH— 51 49 20,800 1.7Comparative 3-5-B (40) Comparative 3-3 B —O—C(═O)—NH— 41 59 21,300 1.7Comparative 3-5-G (50) Comparative 3-3 G —O— 47 53 20,800 1.7Comparative 3-6-A (50) Comparative 3-4 A —O—C(═O)—NH— 51 49 18,800 1.7Comparative 3-6-B (50) Comparative 3-4 B O—C(═O)—NH— 49 51 19,300 1.7Comparative 3-6-G (50) Comparative 3-4 G —O— 52 48 18,800 1.7Comparative 3-7-A (50) Comparative 3-7 A —O—C(═O)—NH— 50 50 11,200 1.5Comparative 3-7-B (50) Comparative 3-7 B —O—C(═O)—NH— 53 47 11,700 1.5Comparative 3-7-G (50) Comparative 3-7 G —O— 52 48 11,200 1.5Comparative 3-8-A (50) Comparative 3-8 A —O—C(═O)—NH— 51 49 14,100 1.5Comparative 3-8-B (45) Comparative 3-8 B —O—C(═O)—NH— 45 55 14,800 1.5Comparative 3-8-G (50) Comparative 3-8 G —O— 52 48 14,000 1.5Comparative 3-9-A (50) Comparative 3-9 A —O—C(═O)—NH— 51 49 20,600 1.7Comparative 3-9-B (40) Comparative 3-9 B O—C(═O)—NH— 39 61 21,600 1.7Comparative 3-9-G (50) Comparative 3-9 G —O— 49 51 20,500 1.7Comparative 3-10-A (50) Comparative 3-10 A O—C(═O)—NH— 50 50 22,300 1.7Comparative 3-10-B (45) Comparative 3-10 B —O—C(═O)—NH— 48 52 23,200 1.7Comparative 3-10-G (50) Comparative 3-10 G —O— 51 49 22,200 1.7Comparative 3-11-A (50) Comparative 3-9 A —O—C(═O)—NH— 52 48 24,400 1.7Comparative 3-11-B (40) Comparative 3-9 B —O—C(═O)—NH— 39 61 25,300 1.7Comparative 3-11-G (50) Comparative 3-9 G —O— 48 52 24,300 1.7Comparative 3-12-A (50) Comparative 3-10 A —O—C(═O)—NH— 51 49 22,000 1.7Comparative 3-12-B (50) Comparative 3-10 B —O—C(═O)—NH— 48 52 23,100 1.7Comparative 3-12-G (50) Comparative 3-10 G —O— 53 47 21,900 1.7

4. Preparation of Photosensitive Resin Compositions [Preparation ofPhotosensitive Resin Compositions 3-1 to 3-82 and ComparativePhotosensitive Resin Compositions 3-1 to 3-36]

The fluororesins or comparative fluororesins produced above, solvents,photopolymerization initiators, crosslinking agents, alkali-solubleresins, naphthoquinonediazide group-containing compounds, and basiccompounds were blended according to Tables 3-6 to 3-11. The resultingsolutions were filtered through a 0.2-μm membrane filter, wherebyphotosensitive resin compositions 3-1 to 3-38 and comparativephotosensitive resin compositions 3-1 to 3-12 were prepared. In thetables, the symbol “-” means no addition of the component.

The following solvents, photopolymerization initiators, crosslinkingagents, alkali-soluble resin, naphthoquinonediazide group-containingcompound, and basic compound were used.

Solvents:

S-1: propylene glycol monomethyl ether acetate (PGMEA); S-2:γ-butyrolactone; S-3: propylene glycol monomethyl ether (PGME); S-4:methyl ethyl ketone; S-5: cyclohexanone; S-6: ethyl lactate; S-7: butylacetate photopolymerization initiator; Ini-1: 4-benzoyl benzoic acid;Ini-2: Irgacure 651 (a product of BASF); Ini-3: Irgacure 369 (a productof BASF)

Crosslinking Agents:

CL-1: pentaerythritol tetraacrylate (a product of Tokyo ChemicalIndustry Co., Ltd.); CL-2: A-TMM-3 (a product of Shin-Nakamura ChemicalCo., Ltd.)

Alkali-Soluble Resin:

ASP-1: CCR-1235 (a product of Nippon Kayaku Co., Ltd.)

Naphthoquinonediazide Group-Containing Compound:

N-1: naphthoquinone-1,2-diazide-5-sulfonate compound (PC-5, a product ofToyo Gosei Co., Ltd.)

Basic Compound:

B-1: triethanolamine (a product of Tokyo Chemical Industry Co., Ltd.)

TABLE 3-6 Naphthoquinonediazide Photopolymerization CrosslinkingAlkali-soluble group-containing Photosensitive Fluororesin Solventinitiator agent resin compound Basic compound resin Parts Parts PartsParts Parts Parts Parts composition by by by by by by by No. Type massType mass Type mass Type mass Type mass Type mass Type mass 3-1  3-1-A(50) 1.0 S-1 65 Ini-2 7.5 — — — — — — — — S-3 35 3-2  3-1-A (50) 1.0 S-170 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 30 3-3   3-1-A (100) 1.0 S-7100 Ini-3 7.5 — — — — — — — — 3-4   3-1-A (100) 1.0 S-1 65 Ini-2 5.0CL-2 25 ASP-1 50 N-1 10 B-1 0.5 S-3 35 3-5  3-1-B (50) 1.0 S-4 100 Ini-17.5 — — — — — — — — 3-6  3-1-B (50) 0.5 S-1 65 Ini-2 7.5 CL-1 50 ASP-150 — — — — S-3 35 3-7  3-1-G (50) 1.0 S-6 100 Ini-1 7.5 — — — — — — — —3-8  3-1-G (50) 1.0 S-1 70 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 303-9  3-2-A (50) 1.0 S-4 100 Ini-3 7.5 — — — — — — — — 3-10 3-2-A (50)1.0 S-1 50 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 50 3-11 3-2-B (50) 1.0S-4 100 Ini-2 7.5 — — — — — — — — 3-12 3-2-B (50) 0.8 S-1 55 Ini-3 7.5CL-1 50 ASP-1 50 N-1 10 B-1 0.5 S-3 45 3-13 3-2-G (50) 1.0 S-4 100 Ini-37.5 — — — — — — — — 3-14 3-2-G (50) 1.0 S-1 60 Ini-3 7.5 CL-1 50 ASP-150 — — — — S-3 40 3-15 3-3-A (50) 1.0 S-4 100 Ini-2 7.5 — — — — — — — —3-16 3-3-A (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 403-17 3-3-B (40) 1.0 S-4 100 Ini-1 7.5 — — — — — — — — 3-18 3-3-B (40)1.5 S-1 80 Ini-3 7.5 CL-1 50 ASP-1 45 — — — — S-3 20 3-19 3-3-G (50) 1.0S-4 100 Ini-3 7.5 — — — — — — — — 3-20 3-3-G (50) 1.0 S-1 70 Ini-2 7.5CL-1 65 ASP-1 50 N-1 10 B-1 0.5 S-3 30

TABLE 3-7 Naphthoquinonediazide Photopolymerization CrosslinkingAlkali-soluble group-containing Photosensitive Fluororesin Solventinitiator agent resin compound Basic compound resin Parts Parts PartsParts Parts Parts Parts composition by by by by by by by No. Type massType mass Type mass Type mass Type mass Type mass Type mass 3-21 3-4-A(50) 0.8 S-7 100 Ini-1 7.5 — — — — — — — — 3-22 3-4-A (50) 1.0 S-1 70Ini-3 7.5 CL-1 50 ASP-1 50 — — — — S-3 30 3-23 3-4-B (40) 1.0 S-1 100Ini-2 7.5 — — — — — — — — 3-24 3-4-B (40) 1.0 S-1 60 Ini-2 7.5 CL-2 70ASP-1 40 — — — — S-3 40 3-25 3-4-G (50) 1.0 S-7 100 Ini-3 7.5 — — — — —— — — 3-26 3-4-G (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-340 3-27 3-5-A (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 403-28 3-5-B (45) 1.0 S-8 100 Ini-2 7.5 — — — — — — — — 3-29 3-5-B (45)1.0 S-1 70 Ini-1 7.5 CL-2 30 ASP-1 50 N-1 10 B-1 0.5 S-3 30 3-30 3-5-G(50) 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 60 N-1 10 B-1 0.5 S-3 30 3-313-6-A (50) 0.5 S-1 100 Ini-2 7.5 — — — — — — — — 3-32 3-6-A (50) 1.0 S-165 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 35 3-33 3-6-B (40) 1.0 S-1 100Ini-3 7.5 — — — — — — — — 3-34 3-6-B (40) 1.5 S-7 100 Ini-3 7.5 CL-2 75ASP-1 70 — — — — 3-35 3-6-G (50) 1.3 S-5 100 Ini-2 5.0 CL-2 50 ASP-1 50— — — — 3-36 3-7-A (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — —S-3 40 3-37 3-7-B (45) 0.8 S-7 100 Ini-3 7.5 CL-1 75 ASP-1 70 — — — —3-38 3-7-G (50) 1.0 S-5 100 Ini-2 7.5 CL-2 75 ASP-1 50 — — — — 3-393-8-A (50) 1.5 S-1 70 Ini-3 5.0 CL-1 50 ASP-1 50 — — — — S-3 30 3-403-8-B (41) 1.0 S-7 100 Ini-3 7.5 CL-1 75 ASP-1 70 — — — — 3-41 3-8-G(51) 1.0 S-5 100 Ini-3 7.5 CL-2 50 ASP-1 50 — — — —

TABLE 3-8 Naphthoquinonediazide Photopolymerization CrosslinkingAlkali-soluble group-containing Basic Photosensitive Fluororesin Solventinitiator agent resin compound compound resin Parts Parts Parts PartsParts Parts Parts composition by by by by by by by No. Type mass Typemass Type mass Type mass Type mass Type mass Type mass 3-42  3-9-A (50)1.0 S-1 65 Ini-2 7.5 — — — — — — — — S-3 35 3-43  3-9-A (50) 1.0 S-1 70Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 30 3-44  3-9-A (100) 1.0 S-7 100Ini-3 7.5 — — — — — — — — 3-45  3-9-A (100) 1.0 S-1 65 Ini-2 5.0 CL-2 25ASP-1 50 N-1 10 B-1 0.5 S-3 35 3-46  3-9-B (50) 1.0 S-4 100 Ini-1 7.5 —— — — — — — — 3-47  3-9-B (50) 0.5 S-1 65 Ini-2 7.5 CL-1 50 ASP-1 50 — —— — S-3 35 3-48  3-9-G (50) 1.0 S-6 100 Ini-1 7.5 — — — — — — — — 3-49 3-9-G (50) 1.0 S-1 70 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 30 3-503-10-A (50) 1.0 S-4 100 Ini-3 7.5 — — — — — — — — 3-51 3-10-A (50) 1.0S-1 50 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 50 3-52 3-10-B (50) 1.0S-4 100 Ini-2 7.5 — — — — — — — — 3-53 3-10-B (50) 0.8 S-1 55 Ini-3 7.5CL-1 50 ASP-1 50 N-1 10 B-1 0.5 S-3 45 3-54 3-10-G (50) 1.0 S-4 100Ini-3 7.5 — — — — — — — — 3-55 3-10-G (50) 1.0 S-1 60 Ini-3 7.5 CL-1 50ASP-1 50 — — — — S-3 40 3-56 3-11-A (50) 1.0 S-4 100 Ini-2 7.5 — — — — —— — — 3-57 3-11-A (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-340 3-58 3-11-B (40) 1.0 S-4 100 Ini-1 7.5 — — — — — — — — 3-59 3-11-B(40) 1.5 S-1 80 Ini-3 7.5 CL-1 50 ASP-1 45 — — — — S-3 20 3-60 3-11-G(50) 1.0 S-4 100 Ini-3 7.5 — — — — — — — — 3-61 3-11-G (50) 1.0 S-1 70Ini-2 7.5 CL-1 65 ASP-1 50 N-1 10 B-1 0.5 S-3 30

TABLE 3-9 Naphthoquinonediazide Photopolymerization CrosslinkingAlkali-soluble group-containing Basic Photosensitive Fluororesin Solventinitiator agent resin compound compound resin Parts Parts Parts PartsParts Parts Parts composition by by by by by by by No. Type mass Typemass Type mass Type mass Type mass Type mass Type mass 3-62 3-12-A (50)0.8 S-7 100 Ini-1 7.5 — — — — — — — — 3-63 3-12-A (50) 1.0 S-1 70 Ini-37.5 CL-1 50 ASP-1 50 — — — — S-3 30 3-64 3-12-B (40) 1.0 S-1 100 Ini-27.5 — — — — — — — — 3-65 3-12-B (40) 1.0 S-1 60 Ini-2 7.5 CL-2 70 ASP-140 — — — — S-3 40 3-66 3-12-G (50) 1.0 S-7 100 Ini-3 7.5 — — — — — — — —3-67 3-12-G (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 403-68 3-13-A (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 403-69 3-13-B (45) 1.0 S-8 100 Ini-2 7.5 — — — — — — — — 3-70 3-13-B (45)1.0 S-1 70 Ini-1 7.5 CL-2 30 ASP-1 50 N-1 10 B-1 0.5 S-3 30 3-71 3-13-G(50) 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 60 N-1 10 B-1 0.5 S-3 30 3-723-14-A (50) 0.5 S-1 100 Ini-2 7.5 — — — — — — — — 3-73 3-14-A (50) 1.0S-1 65 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — S-3 35 3-74 3-14-B (40) 1.0S-1 100 Ini-3 7.5 — — — — — — — — 3-75 3-14-B (40) 1.5 S-7 100 Ini-3 7.5CL-2 75 ASP-1 70 — — — — 3-76 3-14-G (50) 1.3 S-5 100 Ini-2 5.0 CL-2 50ASP-1 50 — — — — 3-77 3-15-A (50) 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50— — — — S-3 40 3-78 3-15-B (45) 0.8 S-7 100 Ini-3 7.5 CL-1 75 ASP-1 70 —— — — 3-79 3-15-G (50) 1.0 S-5 100 Ini-2 7.5 CL-2 75 ASP-1 50 — — — —3-80 3-16-A (50) 1.5 S-1 70 Ini-3 5.0 CL-1 50 ASP-1 50 — — — — S-3 303-81 3-16-B (41) 1.0 S-7 100 Ini-3 7.5 CL-1 75 ASP-1 70 — — — — 3-823-16-G (51) 1.0 S-5 100 Ini-3 7.5 CL-2 50 ASP-1 50 — — — —

TABLE 3-10 Naphthoquinonediazide Comparative ComparativePhotopolymerization Crosslinking Alkali-soluble group-containing Basicphotosensitive fluororesin Solvent initiator agent resin compoundcompound resin Parts Parts Parts Parts Parts Parts Parts composition byby by by by by by No. Type mass Type mass Type mass Type mass Type massType mass Type mass 3-1  Comparative 1.0 S-1 68 Ini-2 7.5 CL-1 50 ASP-150 — — — — 3-1-A (50) S-3 32 3-2  Comparative 1.0 S-3 100 Ini-1 7.5 CL-150 ASP-1 50 N-1 10 B-1 0.5 3-1-B (50) 3-3  Comparative 1.0 S-4 100 Ini-17.5 CL-1 50 ASP-1 50 — — — — 3-1-G (50) 3-4  Comparative 1.0 S-1 50Ini-2 7.5 CL-1 50 ASP-1 50 — — — — 3-2-A (50) S-3 50 3-5  Comparative1.0 S-1 55 Ini-3 7.5 CL-1 50 ASP-1 50 N-1 10 B-1 0.5 3-2-B (45) S-3 453-6  Comparative 1.0 S-7 100 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — 3-2-G(50) 3-7  Comparative 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — —3-3-A (50) S-3 40 3-8  Comparative 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 50N-1 10 B-1 0.5 3-3-B (40) S-3 30 3-9  Comparative 1.0 S-1 100 Ini-3 7.5CL-1 50 ASP-1 50 — — — — 3-3-G (50) 3-10 Comparative 1.0 S-1 100 Ini-37.5 CL-1 50 ASP-1 50 — — — — 3-4-A (50) 3-11 Comparative 1.0 S-1 60Ini-2 7.5 CL-2 50 ASP-1 50 — — — — 3-4-B (45) S-3 40 3-12 Comparative1.0 S-1 70 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — 3-4-G (50) S-3 30 3-13Comparative 1.0 S-1 65 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — 3-5-A (50) S-335 3-14 Comparative 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — 3-5-B(40) S-3 30 3-15 Comparative 1.0 S-1 100 Ini-3 7.5 CL-1 50 ASP-1 50 — —— — 3-5-G (50) 3-16 Comparative 1.0 S-1 65 Ini-2 7.5 CL-1 50 ASP-1 50 —— — — 3-6-A (50) S-3 35 3-17 Comparative 1.0 S-1 60 Ini-2 7.5 CL-2 50ASP-1 50 N-1 10 B-1 0.5 3-6-B (50) S-3 40 3-18 Comparative 1.0 S-1 60Ini-3 7.5 CL-1 50 ASP-1 50 — — B-1 0.5 3-6-G (50) S-3 40

TABLE 3-11 Naphthoquinonediazide Comparative ComparativePhotopolymerization Crosslinking Alkali-soluble group-containing Basicphotosensitive fluororesin Solvent initiator agent resin compoundcompound resin Parts Parts Parts Parts Parts Parts Parts composition byby by by by by by No. Type mass Type mass Type mass Type mass Type massType mass Type mass 3-19 Comparative 1.0 S-1 68 Ini-2 7.5 CL-1 50 ASP-150 — — — — 3-7-A (50) S-3 32 3-20 Comparative 1.0 S-3 100 Ini-1 7.5 CL-150 ASP-1 50 N-1 10 B-1 0.5 3-7-B (50) 3-21 Comparative 1.0 S-4 100 Ini-17.5 CL-1 50 ASP-1 50 — — — — 3-7-G (50) 3-22 Comparative 1.0 S-1 50Ini-2 7.5 CL-1 50 ASP-1 50 — — — — 3-8-A (50) S-3 50 3-23 Comparative1.0 S-1 55 Ini-3 7.5 CL-1 50 ASP-1 50 N-1 10 B-1 0.5 3-8-B (45) S-3 453-24 Comparative 1.0 S-7 100 Ini-3 7.5 CL-1 50 ASP-1 50 — — — — 3-8-G(50) 3-25 Comparative 1.0 S-1 60 Ini-2 7.5 CL-1 50 ASP-1 50 — — — —3-9-A (50) S-3 40 3-26 Comparative 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 50N-1 10 B-1 0.5 3-9-B (40) S-3 30 3-27 Comparative 1.0 S-1 100 Ini-3 7.5CL-1 50 ASP-1 50 — — — — 3-9-G (50) 3-28 Comparative 1.0 S-1 100 Ini-37.5 CL-1 50 ASP-1 50 — — — — 3-10-A (50) 3-29 Comparative 1.0 S-1 60Ini-2 7.5 CL-2 50 ASP-1 50 — — — — 3-10-B (45) S-3 40 3-30 Comparative1.0 S-1 70 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — 3-10-G (50) S-3 30 3-31Comparative 1.0 S-1 65 Ini-2 7.5 CL-1 50 ASP-1 50 — — — — 3-11-A (50)S-3 35 3-32 Comparative 1.0 S-1 70 Ini-3 7.5 CL-1 50 ASP-1 50 — — — —3-11-B (40) S-3 30 3-33 Comparative 1.0 S-1 100 Ini-3 7.5 CL-1 50 ASP-150 — — — — 3-11-G (50) 3-34 Comparative 1.0 S-1 65 Ini-2 7.5 CL-1 50ASP-1 50 — — — — 3-12-A (50) S-3 35 3-35 Comparative 1.0 S-1 60 Ini-27.5 CL-2 50 ASP-1 50 N-1 10 B-1 0.5 3-12-B (50) S-3 40 3-36 Comparative1.0 S-1 60 Ini-3 7.5 CL-1 50 ASP-1 50 — — B-1 0.5 3-12-G (50) S-3 405. Evaluation of Liquid Repellency of Each Fluororesin Film Before andafter UV-Ozone Treatment and after Heating Step

[Formation of Fluororesin Films 3-1 to 3-82 and Comparative FluororesinFilms 3-1 to 3-36]

The photosensitive resin compositions 3-1 to 3-82 and comparativephotosensitive resin compositions 3-1 to 3-36 prepared were each appliedto a silicon wafer using a spin coater at a rotation speed of 1000 rpm.Subsequently, these resin compositions were heated on a hot plate at100° C. for 150 seconds, whereby fluororesin films 3-1 to 3-82 andcomparative fluororesin films 3-1 to 3-36 (the numbers correspond to therespective numbers of the photosensitive resin compositions) were eachformed on the silicon wafer.

The fluororesin films 3-2, 3-10, 3-16, 3-22, 3-27, 3-32, 3-36, 3-39,3-43, 3-51, 3-57, 3-63, 3-68, 3-73, 3-77, and 3-80 and the comparativefluororesin films 3-1, 3-4, 3-7, 3-10, 3-13, 3-16, 3-19, 3-22, 3-25,3-28, 3-31, and 3-34 obtained above were subjected to contact anglemeasurement with respect to water, anisole, and methyl benzoate beforeand after UV-ozone treatment and after heating. Water, anisole, andmethyl benzoate were used as ink solvents.

[UV-Ozone Treatment Step and Heating Step]

The fluororesin films and comparative fluororesin films on the siliconwafer were each subjected to UV-ozone treatment for 10 minutes using aUV-ozone treatment device (available from Sen Lights Corporation; modelnumber: PL17-110). Subsequently, heating was performed at 230° C. for 60seconds.

[Contact Angle Measurement]

With a contact angle meter “DMs-601” available from Kyowa InterfaceScience Co., Ltd., each fluororesin film surface and each comparativefluororesin film surface were subjected to contact angles measurementwith respect to water, anisole, and methyl benzoate before and after theUV-ozone treatment and after the subsequent heating step.

[Film Thickness Measurement]

Using a stylus-type surface shape measuring instrument “Dektak-8”available from Bruker Nano, the thickness of each of the fluororesinfilms and comparative fluororesin films was measured before and afterthe UV-ozone treatment and after the subsequent heating step.

[Measurement of Molecular Weight Changes]

The fluororesin films and the comparative fluororesin films were eachscraped off with a spatula, and each resulting solid was dissolved inTHF to determine the molecular weight by GPC before and after theUV-ozone treatment and after the subsequent heating step. The tableshows multiple molecular weights with “multiple” in the cases wheremultiple peaks were detected.

Tables 3-12 and 3-13 show the results of the contact angle measurement.Tables 3-14 and 3-15 show the results of the film thickness measurementand weight average molecular weight (Mw) in each step.

TABLE 3-12 Contact angle (°) Photosensitive Anisole Methyl benzoateWater resin UV-ozone After UV-ozone After UV-ozone After Fluororesincomposition treatment heating treatment heating treatment heating filmNo. No. Before After step Before After step Before After step 3-2  3-2 69 52 68 69 51 57 106 87 105 3-10 3-10 71 39 70 71 35 69 106 98 105 3-163-16 68 44 68 67 42 66 105 96 104 3-22 3-22 72 38 68 71 31 70 105 98 1043-27 3-27 66 44 65 65 28 64 103 96 103 3-32 3-32 67 34 65 68 31 65 10395 103 3-36 3-36 68 47 67 67 38 66 105 95 104 3-39 3-39 67 46 65 67 3665 104 95 103 3-43 3-43 67 52 66 70 52 57 106 86 105 3-51 3-51 72 42 7072 40 70 105 97 104 3-57 3-57 68 48 67 66 48 66 103 96 103 3-63 3-63 7443 69 72 53 75 104 97 103 3-68 3-68 70 49 68 67 38 65 103 97 103 3-733-73 67 48 66 69 53 65 104 95 103 3-77 3-77 69 50 68 68 46 66 104 94 1043-80 3-80 68 51 67 68 49 67 104 96 102

TABLE 3-13 Contact angle (°) Photosensitive Anisole Methyl benzoateWater resin UV-ozone After UV-ozone After UV-ozone After Fluororesincomposition treatment heating treatment heating treatment heating filmNo. No. Before After step Before After step Before After stepComparative 3-1 Comparative 3-1 77 47 46 74 32 28 106 33 21 Comparative3-4 Comparative 3-4 75 43 45 75 31 27 107 37 25 Comparative 3-7Comparative 3-7 68 38 41 65 37 33 107 61 63 Comparative 3-10 Comparative3-10 67 31 21 70 32 25 107 51 40 Comparative 3-13 Comparative 3-13 69 4143 71 38 31 108 54 61 Comparative 3-16 Comparative 3-16 71 37 44 70 2728 108 44 55 Comparative 3-19 Comparative 3-19 77 47 46 74 32 28 106 3321 Comparative 3-22 Comparative 3-22 75 45 42 72 32 29 107 40 28Comparative 3-25 Comparative 3-25 69 40 39 66 40 35 106 60 61Comparative 3-28 Comparative 3-28 68 33 22 69 38 30 105 52 39Comparative 3-31 Comparative 3-31 70 42 42 70 40 36 108 55 60Comparative 3-34 Comparative 3-34 71 39 42 71 33 29 107 46 54

TABLE 3-14 Photosensitive Film thickness (nm) Molecular weight resinUV-ozone After UV-ozone After Fluororesin composition treatment heatingtreatment heating film No. No. Before After step Before After step 3-2 3-2  1100 1045 990 5,600 5,300 5,100 3-10 3-10 1210 1150 1089 5,3005,200 5,000 3-16 3-16 1240 1178 1116 8,000 7,800 7,500 3-22 3-22 11801121 1062 8,300 8,200 7,900 3-27 3-27 1090 1036 981 8,600 8,500 8,3003-32 3-32 1150 1093 1035 8,700 8,600 8,300 3-36 3-36 1130 1074 10178,700 8,600 8,100 3-39 3-39 1200 1140 1080 8,300 8,100 7,500 3-43 3-431120 1064 1008 8,500 8,400 8,100 3-51 3-51 1250 1188 1125 8,200 8,0007,900 3-57 3-57 1270 1207 1143 10,600 10,300 10,000 3-63 3-63 1210 10801080 10,800 10,600 10,100 3-68 3-68 1120 1064 1008 10,800 10,500 10,0003-73 3-73 1470 1340 1230 11,900 11,700 11,300 3-77 3-77 1150 1093 103510,900 10,600 10,200 3-80 3-80 1240 1178 1116 10,300 10,200 9,900

TABLE 3-15 Photosensitive Film thickness (nm) Molecular weight resinUV-ozone After UV-ozone After Fluororesin composition treatment heatingtreatment heating film No. No. Before After step Before After stepComparative 3-1 Comparative 3-1 1250 320 <100 11,200 <1000 <1000multiple multiple Comparative 3-4 Comparative 3-4 1180 400 230 11,700<1000 <1000 multiple multiple Comparative 3-7 Comparative 3-7 1160 480300 16,200 4000, 4000, <1000 <1000 multiple multiple Comparative 3-10Comparative 3-10 1070 370 250 18,800 4200, 3800, <1000 <1000 multiplemultiple Comparative 3-13 Comparative 3-13 1100 400 310 20,800 5000,2000, <1000 <1000 multiple multiple Comparative 3-16 Comparative 3-161030 360 240 18,800 4000, 2800, <1000 <1000 multiple multipleComparative 3-19 Comparative 3-19 1250 320 <100 11,200 <1000 <1000multiple multiple Comparative 3-22 Comparative 3-22 1210 410 240 14,100<1000 <1000 multiple multiple Comparative 3-25 Comparative 3-25 1180 490290 20,600 5000, 5000, <1000 <1000 multiple multiple Comparative 3-28Comparative 3-28 1100 380 260 22,300 5300, 4700, <1000 <1000 multiplemultiple Comparative 3-31 Comparative 3-31 1120 390 310 24,400 6500,3000, <1000 <1000 multiple multiple Comparative 3-34 Comparative 3-341070 380 250 22,000 5300, 3700, <1000 <1000 multiple multiple

According to the results in Tables 3-12 and 3-13, in the fluororesinfilms 3-2, 3-10, 3-16, 3-22, 3-27, 3-32, 3-36, 3-39, 3-43, 3-51, 3-57,3-63, 3-68, 3-73, 3-77, and 3-80 of the present disclosure, the contactangle that decreased after the UV-ozone treatment tended to be restoredby the subsequent heat treatment step to a degree comparable to thatbefore the UV-ozone treatment. In contrast, in the comparativefluororesin films 3-1, 3-4, 3-7, 3-10, 3-13, 3-16, 3-19, 3-22, 3-25,3-28, 3-31, and 3-34, although a high contact angle was observed beforethe UV-ozone treatment, the contact angle that decreased after thetreatment showed no significant restoration after the heating step.

According to Tables 3-14 and 3-15, in the fluororesin films 3-2, 3-10,3-16, 3-22, 3-27, 3-32, 3-36, 3-39, 3-43, 3-51, 3-57, 3-63, 3-68, 3-73,3-77, and 3-80 of the present disclosure, although a slight decrease infilm thickness was observed after the UV-ozone treatment, the molecularweight of the remaining film was comparable, indicating excellentresistance to the UV-ozone treatment. In contrast, in the comparativefluororesin films 3-1, 3-4, 3-7, 3-10, 3-13, 3-16, 3-19, 3-22, 3-25,3-28, 3-31, and 3-34, a significant decrease in film thickness wasconfirmed after the UV-ozone treatment, and the molecular weight of theremaining film significantly decreased as compared to that before theUV-ozone treatment, indicating insufficient resistance to the UV-ozonetreatment.

6. Evaluation of Banks

The photosensitive resin compositions 3-2, 3-6, 3-8, 3-10, 3-14, 3-16,3-26, 3-27, 3-32, 3-36, 3-43, 3-47, 3-49, 3-51, 3-55, 3-57, 3-67, 3-68,3-73, and 3-77 and the comparative photosensitive resin compositions3-1, 3-4, 3-7, 3-12, 3-13, 3-16, 3-19, 3-22, 3-25, 3-30, 3-31, and 3-34obtained in “4. Preparation of photosensitive resin compositions” wereused to form banks 3-2, 3-6, 3-8, 3-10, 3-14, 3-16, 3-26, 3-27, 3-32,3-36, 3-43, 3-47, 3-49, 3-51, 3-55, 3-57, 3-67, 3-68, 3-73, and 3-77 andcomparative banks 3-1, 3-4, 3-7, 3-12, 3-13, 3-16, 3-19, 3-22, 3-25,3-30, 3-31, and 3-34, respectively, and the bank properties wereevaluated and compared. Table 3-16 shows the results of the banks of thepresent disclosure, and Table 3-17 shows the results the comparativebanks. The components used for the above photosensitive resincompositions, except for the fluororesin or comparative fluororesin,were standardized to compare the properties.

[Formation of Banks]

A 10-cm square ITO substrate was washed with ultrapure water and thenacetone. Subsequently, the substrate was subjected to UV-ozone treatmentfor five minutes using the UV-ozone treatment described above. Then, thephotosensitive resin compositions 3-2, 3-6, 3-8, 3-10, 3-14, 3-16, 3-26,3-27, 3-32, 3-36, 3-43, 3-47, 3-49, 3-51, 3-55, 3-57, 3-67, 3-68, 3-73,and 3-77 the comparative photosensitive resin compositions 3-1, 3-4,3-7, 3-12, 3-13, 3-16, 3-19, 3-22, 3-25, 3-30, 3-31, and 3-34 obtainedin “4. Preparation of photosensitive resin compositions” were eachapplied to the UV-ozone-treated substrate using a spin coater at arotation speed of 1000 rpm, followed by heating on a hot plate at 100°C. for 150 seconds. Thus, fluororesin films and comparative fluororesinfilms each having a thickness of 2 μm were formed. Each resulting resinfilm was exposed to i-rays (wavelength: 365 nm) using a mask aligner (aproduct of SUSS MicroTec Group) with a mask having a 5-μm line-and-spacepattern.

The resulting resin film after exposure was subjected to evaluation ofsolubility in a developer, evaluation of bank properties (sensitivityand resolution), and contact angle measurement.

[Solubility in Developer]

The resin film on the ITO substrate after exposure was immersed in analkali developer at room temperature for 80 seconds to evaluate thesolubility in the alkali developer. The alkali developer was a 2.38 mass% tetramethylammonium hydroxide aqueous solution (hereinafter sometimesreferred to as TMAH). The solubility of the banks was evaluated bymeasuring the thickness of the banks after immersion using a contactfilm thickness meter. The banks were determined to be “soluble” whencompletely dissolved, and “insoluble” when the resist film remainedundissolved.

[Resist Properties (Sensitivity and Resolution)]

The optimal exposure Eop (mJ/cm²) for forming banks arranged in theline-and-space pattern was determined and used as an index forsensitivity.

The resulting pattern of banks was observed under a microscope toevaluate the resolution. A pattern without visible line-edge roughnesswas evaluated as “excellent”; a pattern with slightly visible line-edgeroughness was evaluated as “good”; and a pattern with significantline-edge roughness was evaluated as “poor”.

[Contact Angle]

Each substrate having the banks obtained in the above step was heated at230° C. for 60 minutes. Then, the entire substrate surface was subjectedto UV-ozone treatment or oxygen plasma treatment for 10 minutes.Subsequently, heating was performed at 230° C. for 60 seconds. Thecontact angle between the bank or comparative surface and anisole wasmeasured before and after the UV-ozone treatment and after thesubsequent heating step.

The UV-ozone treatment device and the contact angle meter describedabove were used. An oxygen plasma treatment device was Plasma DryCleaner PDC-210 available from Yamato Scientific Co., Ltd. The oxygenplasma treatment was performed at an oxygen gas flow rate of 30 cc/minand an output of 300 W.

TABLE 3-16 Banks 3-2 3-6 3-8 3-10 3-14 3-16 3-26 Photosensitive resincomposition 3-2 3-6 3-8 3-10 3-14 3-16 3-26 Solubility Non-exposedportion Soluble Soluble Soluble Soluble Soluble Soluble Soluble indeveloper Exposed portion Insoluble Insoluble Insoluble InsolubleInsoluble Insoluble Insoluble Resist Sensitivity (mJ/cm²) 102  101  100 101  102  100  103  properties Resolution Excellent Excellent ExcellentExcellent Excellent Excellent Excellent Contact Before UV-ozonetreatment 34 36 33 29 35 36 38 angle (°) After UV-ozone treatment 10 1010 10 10 10 10 Non-exposed After heating step 10 10 10 10 10 10 10portions Contact Before UV-ozone treatment 60 70 71 71 70 69 68 angle(°) After UV-ozone treatment 52 53 52 37 38 45 44 Exposed After heatingstep 68 67 67 70 68 68 67 portions Contact Before oxygen plasmatreatment 33 34 29 25 33 35 37 angle (°) After oxygen plasma treatment10 10 10 10 10 10 10 Non-exposed After heating step 10 10 10 10 10 10 10portionn Contact Before oxygen plasma treatment 70 71 71 71 70 69 68angle (°) After oxygen plasma treatment 40 45 42 30 28 38 33 ExposedAfter heating step 68 66 69 70 69 67 67 portionn Banks 3-27 3-32 3-363-43 3-47 3-49 3-51 Photosensitive resin composition 3-27 3-32 3-36 3-433-47 3-49 3-51 Solubility Non-exposed portion Soluble Soluble SolubleSoluble Soluble Soluble Soluble in developer Exposed portion InsolubleInsoluble Insoluble Insoluble Insoluble Insoluble Insoluble ResistSensitivity (mJ/cm²) 105  105  105  74 74 73 79 properties ResolutionExcellent Excellent Excellent Excellent Excellent Excellent ExcellentContact Before UV-ozone treatment 40 39 38 33 35 31 28 angle (°) AfterUV-ozone treatment 10 10 10 10 10 10 10 Non-exposed After heating step10 10 10 10 10 10 10 portions Contact Before UV-ozone treatment 70 69 7070 71 72 72 angle (°) After UV-ozone treatment 48 45 47 54 53 52 39Exposed After heating step 68 68 69 58 55 56 71 portions Contact Beforeoxygen plasma treatment 37 37 37 31 33 29 26 angle (°) After oxygenplasma treatment 10 10 10 10 10 10 10 Non-exposed After heating step 1010 10 10 10 10 10 portionn Contact Before oxygen plasma treatment 68 6969 71 70 71 72 angle (°) After oxygen plasma treatment 35 35 34 47 46 4331 Exposed After heating step 67 69 68 70 68 69 70 portionn Banks 3-553-57 3-67 3-68 3-73 3-77 Photosensitive resin composition 3-55 3-57 3-673-68 3-73 3-77 Solubility Non-exposed portion Soluble Soluble SolubleSoluble Soluble Soluble in developer Exposed portion Insoluble InsolubleInsoluble Insoluble Insoluble Insoluble Resist Sensitivity (mJ/cm²) 7873 78 75 70 71 properties Resolution Excellent Excellent ExcellentExcellent Excellent Excellent Contact Before UV-ozone treatment 37 35 3939 40 39 angle (°) After UV-ozone treatment 10 10 10 10 10 10Non-exposed After heating step 10 10 10 10 10 10 portions Contact BeforeUV-ozone treatment 73 68 69 69 69 70 angle (°) After UV-ozone treatment41 47 48 55 53 53 Exposed After heating step 69 66 68 67 65 68 portionsContact Before oxygen plasma treatment 34 35 38 37 38 36 angle (°) Afteroxygen plasma treatment 10 10 10 10 10 10 Non-exposed After heating step10 10 10 10 10 10 portionn Contact Before oxygen plasma treatment 72 6669 68 68 68 angle (°) After oxygen plasma treatment 32 40 36 40 42 40Exposed After heating step 70 64 67 67 67 66 portionn

TABLE 3-17 Banks Comparative 3-1 Comparative 3-4 Comparative 3-7Comparative 3-12 Photosensitive resin composition Comparative 3-1Comparative 3-4 Comparative 3-7 Comparative 3-12 Solubility Non-exposedportion Soluble Soluble Soluble Soluble in developer Exposed portionInsoluble Insoluble Insoluble Insoluble Resist Sensitivity (mJ/cm²) 105 103  102  101  properties Resolution Excellent Excellent ExcellentExcellent Contact Before UV-ozone treatment 39 32 33 35 angle (°) AfterUV-ozone treatment 10 10 10 10 Non-exposed Ater heating step 10 10 10 10portions Contact Before UV-ozone treatment 75 74 73 72 angle (°) AterUV-ozone treatment 45 42 41 37 Exposed Ater heating step 34 34 29 35portions Contact Before oxygen plasma treatment 38 35 35 33 angle (°)Ater oxygen plasma treatment 10 10 10 10 Non-exposed Ater heating step10 10 10 10 portions Contact Before oxygen plasma treatment 75 74 72 72angle (°) Ater oxygen plasma treatment 35 30 31 27 Exposed Ater heatingstep 25 25 24 27 portions Banks Comparative 3-13 Comparative3-16Comparative 3-19 Comparative 3-22 Photosensitive resin compositionComparative 3-13 Comparative 3-16 Comparative 3-19 Comparative 3-22Solubility Non-exposed portion Soluble Soluble Soluble Soluble indeveloper Exposed portion Insoluble Insoluble Insoluble Insoluble ResistSensitivity (mJ/cm²) 102  103  105  78 properties Resolution ExcellentExcellent Excellent Excellent Contact Before UV-ozone treatment 32 33 3931 angle (°) After UV-ozone treatment 10 10 10 10 Non-exposed Aterheating step 10 10 10 10 portions Contact Before UV-ozone treatment 7172 75 73 angle (°) Ater UV-ozone treatment 35 35 45 40 Exposed Aterheating step 34 35 34 34 portions Contact Before oxygen plasma treatment33 33 38 33 angle (°) Ater oxygen plasma treatment 10 10 10 10Non-exposed Ater heating step 10 10 10 10 portions Contact Before oxygenplasma treatment 73 72 75 71 angle (°) Ater oxygen plasma treatment 2727 35 30 Exposed Ater heating step 25 25 25 26 portions BanksComparative 3-25 Comparative 3-30 Comparative 3-31 Comparative 3-34Photosensitive resin composition Comparative 3-25 Comparative 3-30Comparative 3-31 Comparative 3-34 Solubility Non-exposed portion SolubleSoluble Soluble Soluble in developer Exposed portion Insoluble InsolubleInsoluble Insoluble Resist Sensitivity (mJ/cm²) 74 77 75 78 propertiesResolution Excellent Excellent Excellent Excellent Contact BeforeUV-ozone treatment 32 36 31 32 angle (°) After UV-ozone treatment 10 1010 10 Non-exposed Ater heating step 10 10 10 10 portions Contact BeforeUV-ozone treatment 71 71 69 71 angle (°) Ater UV-ozone treatment 43 4038 38 Exposed Ater heating step 35 34 36 35 portions Contact Beforeoxygen plasma treatment 34 33 32 33 angle (°) Ater oxygen plasmatreatment 10 10 10 10 Non-exposed Ater heating step 10 10 10 10 portionsContact Before oxygen plasma treatment 67 72 70 71 angle (°) Ater oxygenplasma treatment 35 29 32 28 Exposed Ater heating step 27 27 28 27portions

As shown in Tables 3-16 and 3-17, the evaluation of solubility in thedeveloper shows that the banks and the comparative banks were made of anegative resist in which only the non-exposed portions are soluble. Theevaluation of the bank properties shows that all the banks hadcomparable sensitivity and “excellent” resolution in which the 5-μmline-and-space pattern of the mask was transferred with good resolutionwithout visible line-edge roughness. Specifically, these evaluationsshow that the fluororesins of the present disclosure and the comparativefluororesins only slightly influenced the banks.

In contrast, in the banks of the present disclosure, although thecontact angle between the exposed portions (corresponding to the uppersurfaces of the banks) and anisole decreased due to the UV-ozonetreatment or oxygen plasma treatment, the contact angle increased due tothe subsequent heating step, indicating good liquid repellency. In thecomparative banks, the contact angle decreased due to the UV-ozonetreatment or oxygen plasma treatment and remained small even after thesubsequent heating step, indicating insufficient liquid repellency.

1-23. (canceled)
 24. A fluororesin comprising: a repeating unitrepresented by a formula (3-1) and a repeating unit represented by aformula (3-2):

wherein R³⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R³⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R³⁻¹, R³⁻³, and R³⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R³⁻⁵ and R³⁻⁶ each independently represent a hydrogen atom or amethyl group; W³ is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A³⁻¹ and A³⁻² are divalent linking groups and each independentlyrepresent a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylenegroup in which one or more hydrogen atoms in the alkylene group may besubstituted by hydroxy groups or —O—C(═O)—CH₃; Y³⁻¹ and Y³⁻² aredivalent linking groups and each independently represent —O— or —NH—; nrepresents an integer of 1 to 3; and r represents 0 or
 1. 25. Thefluororesin according to claim 24, wherein R³⁻³ and R³⁻⁴ eachindependently represent a fluorine atom, a trifluoromethyl group, adifluoromethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethylgroup, an n-heptafluoropropyl group, a 2,2,3,3,3-pentafluoropropylgroup, a 3,3,3-trifluoropropyl group, or a hexafluoroisopropyl group.26. The fluororesin according to claim 24, further comprising arepeating unit represented by a formula (3-3):

wherein R³⁻⁷ represents a hydrogen atom or a methyl group; R³⁻⁸represents a C1-C15 linear, C3-C15 branched, or C3-C15 cyclic alkylgroup in which one or more hydrogen atoms in the alkyl group aresubstituted by fluorine atoms; and the repeating unit has a fluorinecontent of 30 mass % or more.
 27. The fluororesin according to claim 24,further comprising a repeating unit represented by a formula (3-4):

wherein R³⁻⁵, Y³⁻¹, A³⁻¹, and r are the same as R³⁻⁵, Y³⁻¹, A³⁻¹, and rin the formula (3-2), respectively; E³⁻¹ represents a hydroxy group, acarboxy group, or an oxirane group; and s represents 0 or
 1. 28. Thefluororesin according to claim 24, further comprising a repeating unitrepresented by a formula (3-6):

wherein R³⁻⁶ and Y³⁻¹ are the same as R³⁻⁶ and Y³⁻¹ in the formula(3-2), respectively.
 29. The fluororesin according to claim 24, furthercomprising a repeating unit represented by a formula (3-5):

wherein R³⁻⁹ represents a hydrogen atom or a methyl group; each B³independently represents a hydroxy group, a carboxy group,—C(═O)—O—R³⁻¹⁰ wherein R³⁻¹⁰ represents a C1-C15 linear, C3-C15branched, or C3-C15 cyclic alkyl group in which one or more hydrogenatoms in the alkyl group are substituted by fluorine atoms, and R³⁻¹⁰has a fluorine content of 30 mass % or more, or —O—C(═O)—R³⁻¹¹ whereinR³⁻¹¹ represents a C1-C6 linear, C3-C6 branched, or C3-C6 cyclic alkylgroup; and m represents an integer of 0 to
 3. 30. A photosensitive resincomposition at least comprising: the fluororesin according to claim 24;a solvent; and a photopolymerization initiator.
 31. The photosensitiveresin composition according to claim 30, wherein the solvent is at leastone selected from the group consisting of methyl ethyl ketone,cyclohexanone, methyl isoamyl ketone, 2-heptanone, ethylene glycol,ethylene glycol dimethyl ether, ethylene glycol monoacetate, diethyleneglycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether,propylene glycol, propylene glycol monoacetate, propylene glycolmonomethyl ether (PGME), propylene glycol monomethyl ether acetate(PGMEA), dipropylene glycol, dipropylene glycol monoacetate monomethylether, dipropylene glycol monoacetate monoethyl ether, dipropyleneglycol monoacetate monopropyl ether, dipropylene glycol monoacetatemonobutyl ether, dipropylene glycol monoacetate monophenyl ether,1,4-dioxane, methyl lactate, ethyl lactate, methyl acetate, ethylacetate, butyl acetate, methyl methoxypropionate, ethylethoxypropionate, γ-butyrolactone, and hexafluoroisopropyl alcohol. 32.The photosensitive resin composition according to claim 30, furthercomprising a crosslinking agent and an alkali-soluble resin.
 33. Afluororesin film comprising: a repeating unit represented by a formula(3-1) and a repeating unit represented by a formula (3-2A):

wherein R³⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R³⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R³⁻¹, R³⁻³, and R³⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R³⁻⁵ and R³⁻⁶ each independently represent a hydrogen atom or amethyl group; W³ is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A³⁻¹ and A³⁻² are divalent linking groups and each independentlyrepresent a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylenegroup in which one or more hydrogen atoms in the alkylene group may besubstituted by hydroxy groups or —O—C(═O)—CH₃; Y³⁻¹ and Y³⁻² aredivalent linking groups and each independently represent —O— or —NH—; nrepresents an integer of 1 to 3; and r represents 0 or
 1. 34. A bankcomprising: a repeating unit represented by a formula (3-1) and arepeating unit represented by a formula (3-2A):

wherein R³⁻¹ represents a hydrogen atom, a fluorine atom, or a methylgroup; R³⁻² represents a hydrogen atom or a C1-C6 linear, C3-C6branched, or C3-C6 cyclic alkyl group; R³⁻³ and R³⁻⁴ each independentlyrepresent a fluorine atom, a C1-C10 linear, C3-C10 branched, or C3-C10cyclic alkyl group, or a C1-C10 linear, C3-C10 branched, or C3-C10cyclic fluoroalkyl group; and one or more of R³⁻¹, R³⁻³, and R³⁻⁴ arefluorine atoms or the fluoroalkyl groups,

wherein R³⁻⁵ and R³⁻⁶ each independently represent a hydrogen atom or amethyl group; W³ is a divalent linking group and represents —O—,—O—C(═O)—, —C(═O)—O—, —O—C(═O)—NH—, —C(═O)—O—C(═O)—NH—, or —C(═O)—NH—;A³⁻¹ and A³⁻² are divalent linking groups and each independentlyrepresent a C1-C10 linear, C3-C10 branched, or C3-C10 cyclic alkylenegroup in which one or more hydrogen atoms in the alkylene group may besubstituted by hydroxy groups or —O—C(═O)—CH₃; Y³⁻¹ and Y³⁻² aredivalent linking groups and each independently represent —O— or —NH—; nrepresents an integer of 1 to 3; and r represents 0 or
 1. 35. A displayelement comprising: the bank according to claim 34.